Burning of magnesium ribbon in air - Lab Work

September 14, 2016, 12:24 pm

≫ Next: Notes of Ch 6 Natural Vegetation and Wildlife| Class 7th Geography

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To carry out the Burning of magnesium ribbon in air and classify it as physical or chemical changes

Aim

To carry out the Burning of magnesium ribbon in air and classify it as physical or chemical changes

Theory
Physical Change: These changes can be observed and take place without changing the composition of substances. There are no changes in chemical nature of substance. The changes which can be observed are like change in colour, boiling point, melting point, hardness, density, fluidity, rigidity etc. The interconversion of states of matter is also a physical change.

Chemical change: In this change, chemical reaction takes place and completely a new substance with different properties is formed. There are changes in chemical properties and composition of substance.
ex: 2Mg(s) + O₂(g) → 2MgO(s)
Here, the chemical composition and properties of product MgO is totally different from its reactants Mg and O.

Materials Required
Red Litmus Paper, Magnesium Ribbon, China Dish or Watch Glass, Sand Paper, Tongs, Bunsen Burner, Match Box

Procedure 

Step 1: A piece of magnesium ribbon is taken and rubbed with sand paper to remove dust from its surface.
Step 2: Magnesium ribbon is hold with the help of a pair of tongs over the watch glass or china dish.
Step 3: Burning of magnesium ribbon over Bunsen burner is observed and ash is collected in watch glass or china dish.
Step 4: Moist red litmus paper is brought in contact with the white ash collected in watch glass.

Observation Table

Sl. No.	Experiment	Observation	Inference
1.	Magnesium ribbon is rubbed with sand paper.	It looks silvery white.	Colour of magnesium metal is silvery white.
2.	Magnesium Ribbon is burnt.	It burns brilliantly and a white ash is left behind.	Magnesium burns in air to form Magnesium oxide (MgO).
3.	Moist red litmus is brought in contact with the ash of Magnesium ribbon.	Red litmus paper turns blue.	MgO is basic in nature.

Result
1. Magnesium is silvery white metal.
2. Magnesium burns in air in the presence of O₂ to form magnesium oxide.
                  2Mg(s)    +     O₂(g)     →     2MgO(s)
            (Magnesium)    (From air)    (Magnesium oxide)
3. There is direct combination reaction of two elements Mg and O₂
4. Magnesium oxide(MgO) is basic in nature.
5.Formation of MgO is chemical change.

Precautions
1. The surface of magnesium ribbon should be properly cleaned with sand paper.
2. The white ash of magnesium oxide should not be touched.
3. Magnesium ribbon should be held by a pair of tongs while burning it.
4. It is better to use sun glasses to protect eyes from dazzling light of burning magnesium ribbon.

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Notes of Ch 6 Natural Vegetation and Wildlife| Class 7th Geography

September 15, 2016, 12:28 pm

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Study Material and Notes of Ch 6 Natural Vegetation and Wildlife Class 7th Geography

Topics in the Chapter

• Natural Vegetation
• Forests
→ Tropical Evergreen forests
→ Tropical Deciduous forests
→ Temperate Evergreen forests
→ Temperate Deciduous forests
→ Mediterranean Vegetation
→ Coniferous forests
• Grasslands
→ Tropical Grasslands
→ Temperate Grasslands
• Thorny bushes
• Polar region

Natural Vegetation

• Natural Vegetation refers to the plant life of a region which grown naturally.

• The type and thickness of natural vegetation varies from place to place because of the variation in these factors.

• Natural Vegetation is classified into three broad categories:

→ Forests: Which grow where temperature and rainfall are plentiful to support a tree cover.
→ Grasslands: Which grow in the region of moderate rain.
→ Shrubs: Thorny shrurbs and scrubs grow in the dry region.

• The changes in the type of natural vegetation occur mainly because of the changes of climatic condition.

Forests

Tropical Evergreen Forests

• Also called tropical rainforests.

• These thick forests occur in the regions near the equator and close to the tropics.

• These regions are hot and receive heavy rainfall throughout the year.

• As there is no particular dry season, the trees do not shed their leaves altogether. Thus, they are called evergreen.

• Common trees: Hardwood trees like rosewood, ebony, mahogany.

Tropical Deciduous Forests

• These are monsoon forests found in the large part of India, northern Australia and in central
America.

• Trees shed their leaves in the dry season to conserve water.

• Common trees: Hardwood trees like sal, teak, neem and shisham.

• Common Animals: Tigers, lions, elephants, langoors and monkeys.

• Importance of Hardwood trees:

→ useful for making furniture, transport and constructional materials.

Temperate Evergreen Forests

• These forests are located in the mid-latitudinal coastal region.

• Commonly found along the eastern margin of the continents, e.g., In south east, USA, South China and in South East Brazil.

• Common trees: both hard and soft wood trees like oak, pine, eucalyptus, etc.

Temperate Deciduous Forests

• These are present at higher latitudes.

• These are found in the north eastern part of USA, China, New Zealand, Chile and also found in the coastal regions of Western Europe.

• They shed their leaves in the dry season. 

• Common trees: Oak, ash, beech, etc. 

• Common animals: Deer, foxes, wolves

• Birds like pheasants, monals are also found here.

Mediterranean Vegetation

• These are present at west and south west margins of the continents.

• It is mostly found in the areas around the Mediterranean sea in Europe, Africa and Asia which given its name.

• It is also found outside the actual Mediterranean region in California in the USA, south west Africa, south western South America and South west Australia.

• These are found in the areas of hot dry summers and mild rainy winters.

• Common vegetation: Citrus fruits such as oranges, figs, olives and grapes.

• There isn’t much wildlife here.

Coniferous Forests

• These trees are found in higher latitudes (50° – 70°) of Northern hemisphere.

• These are also called as Taiga.

• These forests are also seen in the higher altitudes.

• Common trees: Chir, pine, cedar

• Common animals: Silver fox, mink, polar bear.

• Trees are tall, softwood evergreen trees.

→ The woods of these trees are very useful for making pulp, which is used for manufacturing paper and newsprint.

→ Match boxes and packing boxes are also made from softwood.

Grasslands

Tropical grasslands 

• These occur on either side of the equator and extend till the tropics.

• This vegetation grows in the areas of moderate to low amount of rainfall. 

• The grass can grow very tall, about 3 to 4 metres in height.

• Example: Savannah grasslands of Africa.

• Common animals: Elephants, zebras, giraffes, deer, leopards.

Temperate grasslands

• These are found in the mid- latitudinal zones and in the interior part of the continents.

• Grass here is short and nutritious.

• Common animals:Wild buffaloes, bisons, antilopes.

Thorny bushes

• These are found in the dry desert like regions which are located on the western margins of the continents.

• The vegetation cover is scarce because of scanty rain and scorching heat.

Polar region

• This place is extremely cold.

• The growth of natural vegetation is very limited here.

• Only mosses, lichens and very small shrubs are found here which grows during the very short summer.

→ This is called Tundra type of vegetation.

• This vegetation is found in the polar areas of Europe, Asia and North America.

• The animals have thick fur and thick skin to protect themselves from the cold climatic conditions.

• Common animals: Seal, walruses, musk-oxen, Arctic owl, Polar bear and snow foxes.

NCERT Solutions of the Chapter 6 Natural Vegetation and Wildlife

Reaction of Zinc with dilute sulphuric acid - Lab Work

September 16, 2016, 12:40 pm

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To carry out the Reaction of Zinc with dilute sulphuric acid and classify it as physical or chemical changes

Aim

To carry out the Reaction of Zinc with dilute sulphuric acid and classify it as physical or chemical changes

Theory
Physical Change: These changes can be observed and take place without changing the composition of substances. There are no changes in chemical nature of substance. The changes which can be observed are like change in colour, boiling point, melting point, hardness, density, fluidity, rigidity etc. The interconversion of states of matter is also a physical change.

Chemical change: In this change, chemical reaction takes place and completely a new substance with different properties is formed. There are changes in chemical properties and composition of substance.
ex: 2Mg(s) + O₂(g) → 2MgO(s)
Here, the chemical composition and properties of product MgO is totally different from its reactants Mg and O.

Materials Required
Zinc Granules, Big hard Glass Test Tube, Dilute Sulphuric Acid, Jet Delivery Tube, Stand with Clamp, Cork, Match Stick

Procedure 

Step 1: A big hard glass test tube is taken and fixed with clamp stand..
Step 2: Few pieces of zinc is put in the test tube.
Step 3: Some dilute sulphuric acid is poured in it so that the zinc pieces get immersed in the acid. Step 4: Immediately a cork is fixed, having delivery tube with a fine jet, on the mouth of the test tube. Step 5: A burning matchstick is brought near the mouth of the fine jet.  

Observation
1. After adding dil. H₂SO₄ in the tube a brisk reaction starts and gas bubbles come out.
2. On bringing the flame, the gas coming out of the jet burns instantaneously with a small explosion or pop up sound which shows the presence of hydrogen gas.

Inference
1. The gas produced in the reaction is hydrogen. Zinc reacts with dilute sulphuric acid to produce hydrogen gas (H₂) and zinc sulphate.

                 Zn(s)    +     H₂SO₄(g)     →    ZnSO₄(s)       +          H₂
                (Zinc)    (dil. sulphuric acid)  (Zinc Sulphate)   (Hydrogen gas)
This is an example of displacement reaction of a non-metal by a metal.
2. Zinc is more reactive than hydrogen.

4.ZnSO₄ is different in chemical composition and chemical properties than Zn and H₂SO₄ so it is a chemical change.

Precautions
1. Use the chemicals judiciously.
2. Do not inhale gases evolved directly.
3. Hydrogen gas instantaneously burns with mild explosion. Therefore, a fine jet tube should be used to see the burning of hydrogen.
4. Handle acids and alkalies carefully.

Go to List of Experiments

Reaction of Sodium sulphate with barium chloride in the form of their solutions in water - Lab Work

September 16, 2016, 9:05 pm

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Reaction of Sodium sulphate with barium chloride in the form of their solutions in water and classify it as physical or chemical changes

Aim

To carry out the reaction of Sodium sulphate with barium chloride in the form of their solutions in water it as physical or chemical changes

Theory
Physical Change: These changes can be observed and take place without changing the composition of substances. There are no changes in chemical nature of substance. The changes which can be observed are like change in colour, boiling point, melting point, hardness, density, fluidity, rigidity etc. The interconversion of states of matter is also a physical change.

Chemical change: In this change, chemical reaction takes place and completely a new substance with different properties is formed. There are changes in chemical properties and composition of substance.
ex: 2Mg(s) + O₂(g) → 2MgO(s)
Here, the chemical composition and properties of product MgO is totally different from its reactants Mg and O.

Materials Required
Barium Chloride solution(BaCl₂), Sodium Sulphate Solution(Na₂SO₄), Dil. Hydrochloric acid(HCl), Glass Rod, Conical Flask, Test tubes

Procedure 
Step 1: A small amount of barium chloride solution is taken in a test tube and poured into a conical flask.
Step 2: Then a small amount of sodium sulphate solution is taken in another test tube and added into barium chloride solution taken in the conical flask.
Step3: Both the contents of the conical flask is stirred with the help of glass rod and left undisturbed for some time.
Step 4:  After some time, small amount of dil. HCl is added to the precipitate in the conical flask for better result.

Observation
On adding sodium sulphate to barium chloride, white precipitate is immediately formed which is insoluble in dil.HCl.

Inference
1. Sodium sulphate chemically reacts with barium chloride in the form of their aqueous solution to form a white precipitate of barium sulphate.

           Na₂SO₄(aq)  +   BaCl₂(aq)  →  BaSO₄(s)   +   2NaCl(aq)
                                                     (White precipitate)

 2. This is a double displacement reaction in which sulphate ions are displaced by chloride ions and vice-versa.  
3. The products formed are different from the reactants in chemical composition and chemical properties thus this is the case o chemical change.

Precautions
1. The chemicals should be used carefully.
2. Keep the mouth away from the test tubes.
3. Handle acids and alkalies carefully.

Go to List of Experiments

Heating of copper sulphate crystals - Lab Work

September 17, 2016, 12:47 pm

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To carry out the Heating of copper sulphate crystals and classify it as physical or chemical changes

Aim

To carry out the Heating of copper sulphate crystals and classify it as physical or chemical changes

Theory
Physical Change: These changes can be observed and take place without changing the composition of substances. There are no changes in chemical nature of substance. The changes which can be observed are like change in colour, boiling point, melting point, hardness, density, fluidity, rigidity etc. The interconversion of states of matter is also a physical change.

Chemical change: In this change, chemical reaction takes place and completely a new substance with different properties is formed. There are changes in chemical properties and composition of substance.
ex: Mg(s) + O₂(g) → 2MgO(s)
Here, the chemical composition and properties of product MgO is totally different from its reactants Mg and O.

Materials Required
Copper Sulphate Crystals, Bunsen Burners, Boiling test tubes, Test tubes Holder

Procedure 

Step 1: Small amount of copper sulphate crystals is taken dry boiling test tube.

Step 2: Boiling test tube is hold with test tube holder and heated over flame on Bunsen burner.
Step 3: The colour of copper sulphate crystals is observed after heating for some time.
Step 4: The water droplets along the sides of the boiling tube is noted.
Step 5: The boiling tube is removed from the flame and cool.
Step 6: 2-3 drops of water on the sample of copper sulphate obtained after heating is added.

Observation
1. On heating the copper sulphate crystals, the colour changes from blue to white.
2. There are water droplets on the walls of the boiling tube.
3. On adding 2-3 drops of water white copper sulphate turns blue.

Inference
1. Copper sulphate crystals contain water of crystallisation (CuSO₄.5H₂O).
2. On heating, hydrated copper sulphate loses its water molecule and forms white coloured anhydrous copper sulphate.

               CuSO₄.5H₂O(s)   (heat)→     CuSO₄(s)  +  5H₂O(g)
                 (Blue coloured)              (White coloured)

3. On adding water anhydrous copper sulphate changes to hydrated copper sulphate.
4. It is a reversible chemical change.

Precautions
1. Keep the mouth of the test tube away from your face and also from other classmates.
2. Always use test tube holder while heating the test tube.
3. Take a small quantity of copper sulphate crystals.

Go to List of Experiments

To prepare a mixture and a compound using iron filings and sulphur powder - Lab Work

September 18, 2016, 1:06 pm

≫ Next: Notes of Ch 3 Mineral and Power Resources| Class 8th Geography

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To prepare a mixture and a compound using iron filings and sulphur powder and distinguish between appearance, behaviour towards magnet, behaviour towards carbon disulphide and effect of heat

Aim

To prepare a) a mixture b) a compound
using iron filings and sulphur powder and distinguish between these on the basis of:
(i) appearance, i.e., homogeneity and heterogeneity
(ii) behaviour towards a magnet
(iii) behaviour towards carbon disulphide as a solvent
(iv) effect of heat

Theory
Physical Change: These changes can be observed and take place without changing the composition of substances. There are no changes in chemical nature of substance. The changes which can be observed are like change in colour, boiling point, melting point, hardness, density, fluidity, rigidity etc. The interconversion of states of matter is also a physical change.

Chemical change: In this change, chemical reaction takes place and completely a new substance with different properties is formed. There are changes in chemical properties and composition of substance.
ex: Mg(s) + O₂(g) → 2MgO(s)
Here, the chemical composition and properties of product MgO is totally different from its reactants Mg and O.

Mixture. A mixture is obtained when two or more substances are mixed in any proportion which are physically separable. Each constituent substance keeps its characteristics. It is physical change, no new substance is formed e.g., mixing of sulphur powder with iron Sling.

Compound. It is a pure substance which is composed of two or more elements combined chemically in a fixed ratio such that they can be broken into elements only by chemical means. 

Materials Required
Sulphur powder, Carbon disulphide, Dilute Hydrochloric acid, Iron filings, Magnet, Watch glass, China dish, Test tube, Burner, Tripod stand, Glass rod, Wire Gauze, Match Box

Procedure 
Preparation of mixture using iron filings and sulphur powder:
Step 1: About 14 g of fine iron filings and 8 g of sulphur powder in a big petridish or a beaker is taken.
Step 2: They were mixed well to prepare iron filings and sulphur powder. This mixture is labelled as A.

Preparation of compound using iron filings and sulphur powder:
Step 1: About 14 g of fine iron filings and 8 g of sulphur powder in a china dish is taken.
Step 2: They were mixed well and the content of the china dish is heated, first gently then strongly. Step 3: Content is stirred constantly till a black mass i.e., compound of sulphur and iron is formed. Step 4: After black mass is formed, it is cooled and powdered. This compound is labelled as B.

To distinguish the iron filings and sulphur powder mixture and compound on the basis of:
(i) Appearance i.e., Homogeneity and Heterogeneity: Some powder A (iron filings and sulphur powder mixture) is taken in one watch glass and B black mass (compound) powder is taken in another watch glass. Both of them observed carefully observations are recorded.

(ii) Behaviour towards Magnet:  A small quantity of mixture A in a watch glass is placed and a magnet is moved over it. A small quantity of B (black powder) is taken in another watch glass and the same magnet is moved over it. The magnet is examined and observations are recorded.

(iii) Action of Carbon Disulphide: A small quantity of A in a watch glass is taken and 1 ml of carbon disulphide (CS₂) is added to it. The mixture is observed for sometime and observations are recorded. Now, a small quantity of B is taken in a watch glass and 1 ml of CS₂ is added to it. Observations are recorded.

(iv) Effect of Heat: A small quantity of mixture A in a test tube is taken and heated. Change in mixture after sometime is observed. A small quantity of compound powder B in a test tube is taken and heated for the same period as powder A was heated. Changes are bserved.

Observation Table

Results
1. When iron filings and sulphur powder are mixed, both retain their properties. Hence, mixing of iron and sulphur is a physical change.
2. When iron filings and sulphur powder are mixed and heated they undergo chemical reaction and ferrous sulphide (FeS) is formed which is a new substance with entirely different properties from Fe and S. Therefore, heating of mixture of iron and sulphur powder is a chemical change.

Precautions
1. Heat the mixture of iron and sulphur in the hard glass test tubes only.
2. Care should be taken while heating iron and sulphur.
3. Do not inhale gases evolved directly, for example, hydrogen sulphide.
4. Do not bring carbon disulphide near the burner (carbon disulphide is volatile and its vapour catch fire).

Go to List of Experiments

Notes of Ch 3 Mineral and Power Resources| Class 8th Geography

September 19, 2016, 1:20 pm

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Study Material and Notes of Ch 3 Mineral and Power Resources Class 8th Geography

Topics in the Chapter

• What is Mineral

• Types of Minerals
• Extraction of Minerals

• Distribution of Minerals
→ Asia
→ Europe
→ North America
→ South America
→ Africa 

→ Australia

→ Antarctica

• Distribution in India

• Uses of Minerals

• Conservation of Minerals

• Power Resources

• Conventional Sources
→ Firewood
→ Fossil Fuels
→ Hydel Power

• Non-Conventional Sources of Energy

→ Solar Energy

→ Wind Energy

→ Nuclear Energy

→ Geothermal Energy

→ Tidal Energy

→ Biogas

Mineral

• A naturally occurring substance that has a definite chemical composition is a mineral.

• Minerals are not equally distributed over space.

• Minerals are formed in different types of geological environments, under varying conditions. 

• They are created by natural processes without any human interference.

• They can be identified on the basis of their physical properties such as colour, density, hardness and chemical property such as solubility.

Types of Minerals

• On the basis of composition, minerals are classified mainly as: 

→ Metallic

→ Non-metallic minerals

• Metallic minerals contain metal in raw form.
→ Examples: Iron ore, bauxite, manganese ore.

• Metallic minerals may be ferrous or non-ferrous.
→ Ferrous minerals contains iron. Examples are iron ore, manganese and chromites.
→ Non-ferrous mineral does not contain iron but may contain some other metal such as gold, silver, copper or lead.

• Non-metallic minerals do not contain metals.
→ Examples: Limestone, mica and gypsum and mineral fuels like coal and petroleum.

Extraction of Minerals

• Minerals can be extracted by mining, drilling or quarrying.

• The process of taking out minerals from rocks buried under the earth’s surface is called mining.
→ Minerals that lie at shallow depths are taken out by removing the surface layer; this is known as open-cast mining.
→ The mining in which deep bores, called shafts, have to be made to reach mineral deposits that lie at great depths is called is shaft mining.

• Deep wells are bored to take minerals out is called drilling. Petroleum and natural gas are extracted through drilling method.

• Minerals that lie near the surface are simply dug out, by the process known as quarrying.

Distribution of Minerals

• Minerals occur in different types of rocks such as igneous rocks, metamorphic rocks or sedimentary rocks.

→ Generally, metallic minerals are found in igneous and metamorphic rock formations that form large plateaus.

• Metamorphic examples: Iron-ore in north Sweden, copper and nickel deposits in Ontario, Canada, iron, nickel, chromites and platinum in South Africa.

• Sedimentary rock examples: Limestone deposits of Caucasus region of France, manganese deposits of Georgia and Ukraine and phosphate beds of Algeria

Asia

• China and India have large iron ore deposits.

• The continent produces more than half of the world’s tin.
→ China, Malaysia and Indonesia are among the world’s leading tin producers.

• China also leads in production of lead, antimony and tungsten.

• Asia also has deposits of manganese, bauxite, nickel, zinc and copper.

Europe

• It is the leading producer of iron-ore in the world.
→ Russia, Ukraine, Sweden and France have large deposits of iron ore.

• Minerals deposits of copper, lead, zinc, manganese and nickel are found in eastern Europe and European Russia.

North America

• Mineral deposits in North America are located in three zones:
→ The Canadian region north of the Great Lakes: Iron ore, nickel, gold, uranium and copper
→ The Appalachian region: Coal
→ The mountain ranges of the west: Copper, lead, zinc, gold and silver

South America

• Iron Ore: Brazil

• Copper: Chile and Peru

• Tin: Brazil and Bolivia

• Mineral Oil: Venezuela, Argentina, Chile, Peru and Columbia

• South America also has large deposits of gold, silver, zinc, chromium, manganese, bauxite, mica, platinum, asbestos and diamond.

Africa

• It is the world’s largest producer of diamonds, gold and platinum.

• Gold: South Africa, Zimbabwe and Zaire

• Oil: Nigeria, Libya and Angola.

• Other minerals found in Africa are copper, iron ore, chromium, uranium, cobalt and bauxite.

Australia

• It is the largest producer of bauxite in the world.

• It is a leading producer of gold, diamond, iron ore, tin and nickel.

• It is also rich in copper, lead, zinc and manganese.

• Kalgoorlie and Coolgardie areas of western Australia have the largest deposits of gold.

Antartica

• Deposits of coal in the Transantarctic Mountains and iron near the Prince Charles Mountains of East Antarctica is predicted

• Iron ore, gold, silver and oil are also present in commercial quantities.

Distribution in India

• Iron: Jharkhand, Odisha, Chhattisgarh, Madhya Pradesh, Goa, Maharashtra and Karnataka.

• Bauxite: Jharkhand, Odisha, Chhattisgarh, Madhya Pradesh, Gujarat, Maharashtra and Tamil Nadu.

• Mica: Jharkhand, Bihar, Andhra Pradesh and Rajasthan.
→ India is the largest producer and exporter of mica in the world.

• Copper: Rajasthan, Madhya Pradesh, Jharkhand, Karnataka and Andhra Pradesh.

• Manganese: Maharashtra,  Madhya  Pradesh, Chhattisgarh,  Odisha,  Karnataka  and Andhra Pradesh.

• Limestone: Bihar, Jharkhand, Odisha, Madhya Pradesh, Chhattisgarh, Rajasthan, Gujarat and Tamil Nadu.

• Gold:  Kolar in Karnataka has deposits of gold in India. These mines are among the deepest in
the world which makes mining of this ore a very expensive process.

• Salt:  It is obtained from seas, lakes and rocks. India is one of the world’s leading producers and exporters of salt.

Uses of Minerals

• Minerals are used in many industries.

• Minerals used in various styles for jewellery.

• Copper is another metal used in everything from coins to pipes.

• Silicon, used in the computer industry is obtained from quartz.

• Aluminum obtained from its ore bauxite is  used in automobiles and airplanes, bottling industry, buildings and even in kitchen cookware.

Conservation of Minerals

Why to conserve minerals?

• Minerals are a non-renewable resource.

• It takes thousands of years for the formation and concentration of minerals.

• The rate of formation is much smaller than the rate at which the humans consume these minerals.

How to conserve minerals?

• By reducing wastage in the process of mining.

• Recycling of metals is another way in which the mineral resources can be conserved.

Power Resources

• Power or enrgy is necessary for industry, agriculture, transport, communication and defense.

• Power resources categorised as:
→ Conventional resources
→ Non-conventional resources

Conventional Sources of Energy

• Those sources which have been in common use for a long time are called Conventionals sources of energy.

• Firewood and fossil fuels are the two main conventional energy sources.

Firewood

• It is widely used for cooking and heating. 

• In India, more than fifty per cent of the energy used by villagers comes from fire wood.

Fossil Fuels

• Remains of plants and animals which were buried under the earth for millions of years got converted by the heat and pressure into fossil fuels.

• Coal, petroleum and natural gas are the fossils fuels which are the main sources of conventional energy.

• Fossile fuels are in limited quantities and the rate at which the growing world population is consuming them is far greater than the rate of their formation.

Coal

• Most abundantly found fossil fuel. 

• It is used as a domestic fuel, in industries such as iron and steel, steam engines and to generate electricity. 

→ Electricity from coal is called thermal power. 

• The giant ferns and swamps got buried under the layers of earth millions of years ago converted into Coal. Therefore referred to as Buried Sunshine.

• Producers in the world: China, USA, Germany, Russia, South Africa and France.

• Producers in India: Raniganj, Jharia, Dhanbad and Bokaro in Jharkhand.

Petroleum

• Petroleum is a thick black liquid.

• It is found between the layers of rocks and is drilled from oil fields located in off-shore and coastal areas. 

→ This is then sent to refineries which process the crude oil and produce a variety of products like diesel, petrol, kerosene, wax, plastics and lubricants. 

• Petroleum and its derivatives are called Black Gold as they are very valuable.

• Producers in the world: Iran, Iraq, Saudi Arabia and Qatar, USA, Russia, Venezuela, and Algeria. 

• Producers in India: Digboi in Assam, Bombay High in Mumbai and the deltas of Krishna and Godavari rivers.

Natural Gas

• Natural gas is found with petroleum deposits and is released when crude oil is brought to the surface.

• It can be used as a domestic and industrial fuel. 

• Producers in the world: Russia, Norway, UK and the Netherlands

• Producers in India: Jaisalmer, Krishna Godavari delta, Tripura and some areas off shore in Mumbai.

Why use of Fossile fuels should be checked?

• The sharp increase in our consumption of fossil fuels has led to their depletion at an alarming rate. 

• The toxic pollutants released from burning these fuels are also a cause for concern.

Hydel Power

How Hydel Power is generated?

• Rain water or river water stored in dams is made to fall from heights.→ The falling water flows through pipes inside the dam over turbine blades placed at the bottom of the dam.

→ The moving blades then turn the generator to produce electricity. which is called hydro electricity.

• The water discharged after the generation of electricity is used for irrigation. 

• One fourth of the world’s electricity is produced by hydel power. 

• Producers in the world: Paraguay, Norway, Brazil, and China. 

• Important hydel power stations in India: Bhakra Nangal, Gandhi Sagar, Nagarjunsagar

and Damodar valley projects.

Non-Conventional Sources of Energy

Why we need to use non-conventional sources of energy

• The increasing use of fossil fuels is leading to its shortage.

• It is estimated that if the present rate of consumption continues, the reserves of these fuel will get exhausted. 

• Also it causes environmental pollution. 

Therefore, there is need for using non-conventional sources.

• Examples of non-conventional sources: Solar energy, wind energy, tidal energy.

Solar Energy

• Solar energy trapped from the sun can be used in solar cells to produce electricity.

→ Many of these cells are joined into solar panels to generate power for heating and lighting purpose.

• The technology of utilising solar energy benefits a lot of tropical countries that are blessed with abundant sun shine.

• Solar energy is also used in solar heaters, solar cookers, solar dryers besides being used for community lighting and traffic signals.

Wind Energy

• The high speed winds rotate the wind mill which is connected to a generator to produce electricity.

• Wind farms having clusters of such wind mills are located in coastal regions and in mountain passes where strong and steady winds blow. 

• Windfarms are found in Netherlands, Germany, Denmark, UK, USA and Spain.

Nuclear Power

• Nuclear power is obtained from energy stored in the nuclei of atoms of naturally occurring radio active elements like uranium and thorium. 

→ These fuels undergo nuclear fission in nuclear reactors and emit power. 

• Greatest Producers: USA and Europe.

• Uranium deposits in India: Rajasthan and Jharkhand.

• Thorium is found in large quantities in the Monozite sands of Kerala. 

• Nuclear power stations in India: Kalpakkam in Tamilnadu, Tarapur in Maharastra, Ranapratap Sagar near Kota in Rajasthan, Narora in Uttar Pradesh and Kaiga in Karnataka.

Geothermal Energy

• Heat energy obtained from the earth is called geothermal energy.

• The temperature in the interior of the earth rises steadily as we go deeper.
→ Some times this heat energy may surface itself in the form of hot springs.
→ This heat energy can be used to generate power.

• Geothermal energy in the form of hot springs has been used for cooking, heating and bathing for several years.

• USA has the world’s largest geothermal power plants followed by New Zealand, Iceland, Philippines and Central America.

• In India, geothermal plants are located in Manikaran in Himachal Pradesh and Puga Valley in Ladakh.

Tidal Energy

• Energy generated from tides is called tidal energy.

• Tidal energy can be harnessed by building dams at narrow openings of the sea.
→ During high tide the energy of the tides is used to turn the turbine installed in the dam to produce
electricity.

• Producers in the world: Russia, France and the Gulf of Kachchh in
India have huge tidal mill farms.

Bio Gas

• Organic waste such as dead plant and animal material, animal dung and kitchen waste can be converted into a gaseous fuel called biogas.

• The organic waste is decomposed by bacteria in biogas digesters to emit biogas which is essentially a mixture of methane and carbon dioxide.

• Biogas is an excellent fuel for cooking and lighting and produces huge amount of organic manure each year.

NCERT Solutions of Chapter 3 Mineral and Power Resources

To establish relationship between weight of a rectangular wooden block - Lab Work

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To establish relationship between weight of a rectangular wooden block lying on a horizontal table and the minimum force required to just move it using a spring balance

Aim

To establish relationship between weight of a rectangular wooden block lying on a horizontal table and the minimum force required to just move it using a spring balance.

Theory
1. According to third law of motion, for every action, there is an equal and opposite reaction.
2. When one object exerts a force (action) on another object, then the second object also exerts a force (reaction) on the first.
3. These two forces are always equal in magnitude but in opposite direction.
4. The forces always exist in pairs.
5. The two opposing forces are known as action and reaction forces.
6. The forces of action and reaction always act on two different bodies.

Materials Required
Two identical spring balance, Thread, A pan of known mass, Weight box and A Motionless pulley

Procedure 

Step 1: The range and the least count of the two spring balances is found.
Step 2: Ensured that the two spring balances are identical.
Step 3: The spring balances are checked and the force is measured.
Step 4: The two spring balances are hold vertically and ensured that their pointers are at zero mark.
Step 5: Both spring balances A and B, a pulley and a pan of known mass are arranged with the help of thread.
Step 6: The balance B must be attached to a rigid support.
Step 7: Now, the action and reaction forces are identified. The force which spring balance A exerts on B is action (reading on the scale of spring balance B). The reading on the scale of balance A shows the reaction that spring balance B exerts on A.
Step 8: Some mass M is put on the hanger. The total mass attached to the thread is now (M + m). The readings of both the balances are observed.
Step 9: The same activity as above is repeated with atleast four more masses on the pan of known mass. Table for the observations is formed. 

Observation and Calculations
(i) Range of the two spring balances = .... N or g
(ii) Least count of the spring balance = .... N or g
(iii) Acceleration due to gravity (g) at your place = .... ms^-2
(iv) Mass of the pan (given) m = .... g = .... kg.
(v) Weight of the pan w = m (in kg) × g = .... N

Precautions
1. The spring balances, pointer should are at zero mark.
2. The reading of the two spring balances should be noted only when their position conic to rest.
3.Spring balances should be identical.
4. The thread used should be inextensible.

Go to List of Experiments

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Notes of Ch 7 Human Environment - Settlement, Transport and Communication| Class 7th Geography

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Study Material and Notes of Ch 7 Human Environment - Settlement, Transport and Communication Class 7th Geography

Topics in the Chapter

• Settlements
→ Rural Settlements
→ Urban Settlements
• Transport

→ Roadways

→ Railways

→ Waterways

→ Airways

• Communication

Settlements

• Settlements are places where people build their homes.

• Settlements can be of two types:

→ Temporary: Settlements which are occupied for a short time are called temporary settlements. Example: The people living in deep forests, hot and cold deserts and mountains.

→ Permanent: Settlements which are made to live in for a long time are called permanent settlements. Example: People build homes to live in.

Rural Settlements

• The villages are rural settlement where people are engaged in activities like agriculture, fishing, forestry, crafts work and trading etc.

• Rural settlements can be compact or scattered.

→ A compact settlement is a closely built area of dwellings, wherever flat land is available. 

→ In a scattered settlement dwellings are spaced over an extensive area. This type of settlement
is mostly found in hilly tracts, thick forests, and regions of extreme climate.

• In rural areas, people build houses to suit their environment.
→ In regions of heavy rainfall - houses have slanting roofs.
→ In regions where water accumulates in the rainy season - houses are constructed on a raised
platform or stilts.

→ In the areas of hot climate - Thick mud walled houses with thatched roofs.

Urban Settlements

• The towns are small and the cities are larger urban settlements. 

• In urban areas the people are engaged in manufacturing, trading, and services.

Transport

• Transport is the means by which people and goods move.

• In early days, People had to walk and used animals to carry their goods.

• With the passage of time different means of transport developed but even today people use animals for transport.

→ In India donkeys, mules, bullocks and camels are common. 

→ In the Andes Mountains of South America, llamas are used.

→ In Tibet, yaks are used.

• The four major means of transport are:

→ Roadways

→ Railways

→ Waterways

→ Airways

Roadways

• Roads are most commonly used means of transport especially for short distances.

• Roads are classified into two types: 

→ Metalled (pucca) 

→ Unmetalled (kutcha)

• The plains have a dense network of roads. 

• Roads are also present in terrains like deserts, forests and even high mountains. 

→ Manali-Leh highway in the Himlayan Mountains is one of the highest roadways in the world.

• Roads built underground are called subways/under paths. 

• Flyovers are built over raised structures.

Railways

• The railways carry heavy goods and people over long distances quickly and cheaply. 

• Today, Diesel and electric engines have largely replaced the steam engines. 

In places super fast trains
have been introduced to make the
journey faster. 

• The railway network is well developed over the plain areas.

• With the advanced technological skills railway lines are also bein laid in difficult mountain terrains also. Howver these are lesser in numbers. 

• Indian railway network is well developed and largest in Asia.

Waterways

• Waterways are the cheapest for carrying heavy and bulky goods over long distances.

• These are mainly of two types 

→ Inland waterways 

→ Sea routes

Inland Waterways

• Navigable rivers and lakes are used as inland waterways. 

• Important inland waterways: Ganga-Brahmaputra river system, the Great Lakes in North America and the river Nile in Africa.

Sea Routes

• Sea routes and oceanic routes are mostly used for transporting merchandise and goods from one country to another. 

→ These routes are connected with the ports.

• Important ports of the world: Singapore and Mumbai in Asia, New York, Los Angeles in North America, Rio de Janerio in South America, Durban and Cape Town in Africa, Sydney in Australia, London and Rotterdam in Europe.

Airways

• Airways is the fastest way of transport developed in the early twentieth century. 

• It is also the most expensive due to high cost of fuels. 

• Air traffic is adversely affected by bad weather like fog and storms. 

• It is the only mode of transport to reach the most remote and distant areas especially where there are no roads and railways.

• Helicopters are extremely useful in most inaccessible areas and in time of calamities for rescuing people and distributing food, water, clothes and medicines.

• Important airports are Delhi, Mumbai, New York, London, Paris, Frankfurt and Cairo.

Communication

• Communication is the process of conveying messages to others.

• The advancement in the field of communication has brought about an information revolution in the world.

• Different modes of communication are used to provide information, to educate as well as to entertain. 

• Newspapers, radio and television are called mass media as they can communicate
with a large number of people.

Satellites

• The satellites have made communication even faster. 

• Satellites have helped in oil exploration, survey of forest, underground water, mineral wealth, weather forecast and disaster warning. 

• Wireless telephonic communications through cellular phones have become very popular today. 

Internet

• We can send electronic mails or e-mails through Internet.

• Internet provides us with worldwide information and interaction 

• We can also reserve tickets for railways, airways and even cinemas and hotels sitting at home.

NCERT Solutions of Chapter 7 Human Environment - Settlement, Transport and Communication

Notes of Ch 6 Human Resources| Class 8th Geography

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Study Material and Notes of Ch 6 Human Resources Class 8th Geography

Topics in the Chapter

• Introduction
• Distribution of Population
• Density of Population
• Factors affecting distribution of Population
→ Geographical Factors
→ Social, Cultural and Economic Factors
• Population Change
• Patterns of Population Change
• Population Composition

Introduction

• People with their demands and abilities are considered as Human Resources.

• Human resources like other resources are not equally distributed over the world.
→ They differ in their educational levels, age and sex. Their numbers and characteristics also keep changing.

Distribution of Population

• The way in which people are spread across the earth surface is known as the pattern of population distribution.

• The distribution of population in the world is extremely uneven.
→ More than 90 per cent of the world’s population lives in about 30 percent of the land surface.

• Crowded areas: South and south east Asia, Europe and north eastern North America.

• Almost three-quarters of the world’s people live in two continents Asia and Africa.

• Sixty percent of the world’s people live in just 10 countries.→ These are China, India, USA, Indonesia, Brazil, Pakistan, Bangladesh, Nigeria, Russian Fed. and Japan.

Density of Population

• Population density is the number of people living in a unit area of the earth’s surface.
→ It is normally expressed as per square km.

• The average density of population in the whole world is 51 persons per square km. 

• South Central Asia has the highest density of population.

Factors affecting distribution of Population

Geographical Factors

• Topography: People always prefer to live on plains rather than mountains and plateaus because these areas are suitable for farming, manufacturing and service activities.

→ Example: The Ganga plains are the most densely populated areas of the world while mountains like Andes, Alps and Himalayas are sparsely populated.

• Climate: People usually avoid extreme climates that are very hot or very cold.
→ Example: Sahara desert is very hot and polar regions of Russia, Canada and Antarctica are cold are sparsely populated.

• Soil: Fertile soils provide suitable land for agriculture.
→ Example: Fertile plains such as Ganga and Brahmaputra in India, Hwang-He, Chang Jiang in China and the Nile in Egypt are densely populated.

• Water: People prefer to live in the areas where fresh water is easily available.
→ Example: The river valleys of the world are densely populated while deserts have spare population.

• Minerals: Areas with mineral deposits are more populated.
→ Example: Diamond mines of South Africa and discovery of oil in the Middle east lead to settling of people in these areas.

Social, Cultural and Economic Factors

• Social: Areas of better housing, education and health facilities are more densely populated.
→ Example: Pune.

• Cultural: Places with religion or cultural significance attract people.
→ Example: Varanasi, Jerusalem and Vatican city.

• Economic: Industrial areas attract large number of people as it provide employment opportunities. → Example: Osaka in Japan and Mumbai in India.

Population Change

• Population change refers to change in the number of people during a specific time.

• The change happens due to changes in the number of births and deaths.

• Until the 1800s, the world’s population grew steadily but slowly

→ Large numbers of babies were born, but they died early too as there were no proper health facilities.

→ Also, Sufficient food was not available for all the people.

• In 1804, the world’s population reached one billion.

• In 1959, the world’s population reached 3 billion which is often called population explosion.

• In 1999, 40 years later, the population doubled to 6 billion.

→ The main reason for this growth was that with better food supplies and medicine, deaths were reducing, while the number of births still remained fairly high.

Natural Growth Rate

• Birth rate: The number of live births per 1,000 people.

• Death rate: The number of deaths per 1,000 people. 

• Migrations is the movement of people in and out of an area.

• The difference between the birth rate and the death rate of a country is called the natural growth rate.

• The population increase in the world is mainly due to rapid increase in natural growth rate.

Migration

• Migration is another way by which population size changes.

• Emigrants are people who leave a country.
→ Countries like the United States of America and Australia have gained in-numbers by in-migration or immigration.

• Immigrants are those who arrive in a country.
→ Sudan is an example of a country that has experienced a loss in population numbers due to out-migration or emigration.

Patterns of Population Change

• Rates of population growth vary across the world.

• Countries like Kenya have high population growth rates as they had both high birth rates and death rates.

• Countries like United Kingdom, population growth is slowing because of both low death and low birth rates.

Population Composition

• Population composition refers to the structure of the population.

→ It tells about age, sex, literacy level, health condition, occupation and income level of population.

• Population pyramid, also called an age-sex pyramid is a way to study the population composition of a country.

• A population pyramid shows
→ The total population divided into various age groups, example: 5 to 9 years, 10 to 14 years.

→ The percentage of the total population, subdivided into males and females, in each of those groups.

• There are two groups of dependents 

→ Young dependents (aged below 15 years)
→ Elderly dependents (aged over 65 years)

• Those between the age of 15 years and 65 years are working age and are the economically active.

• The population pyramid tells us how many dependents there are in a country.

• The population pyramid of a country in which birth and death rates both are high is broad at the base and rapidly narrows towards the top because although, many children are born, a large percentage of them die in their infancy, relatively few become adults and there are very few old people.

→ Example: Kenya.

• The countries where death rates (especially amongst the very young) are decreasing, the pyramid
is broad in the younger age groups, because more infants survive to adulthood.

→ These countries contain a relatively large number of young people and which means a strong and expanding labour force.

→ Example: India.

• The countries where death rates are decreasing allow numbers of people to reach old age.

→ Example: Japan.

NCERT Solutions of Chapter 6 Human Resources

Notes of Ch 8 Human Environment Interactions: The tropical and subtropical regions| Class 7th Geography

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Study Material and Notes of Ch 8 Human Environment Interactions: The tropical and subtropical regions Class 7th Geography

Topics in the Chapter

• Life in the Amazon Basin

• Climate 

• Rainforests

• People of the Rainforests

• Life in the Ganga-Brahmaputra Basin

Life in the Amazon Basin

• The river Amazon flows through the tropical region lies very close to the equator; between 10°N and 10°S.

→ It is referred to as the equatorial region.

• The place where a river flows into another body of water is called the river’s mouth.

• Numerous tributaries join the Amazon River to form the Amazon basin. 

• The river basin drains portions of Brazil, parts of Peru, Bolivia, Ecuador, Columbia and a small part of Venezuela.

Climate of Amazon Basin

• The Amazon Basin is characterized by hot and wet climate throughout the year as it is present on the equator.

• Both day and nights are almost equally hot and humid. 

• The skin feels sticky. 

• It rains almost everyday, that too without much warning. 

• The day temperatures are high with very high humidity. 

→ At night the temperature goes down but the humidity remains high.

Rainforests in Amazon Basin

• Thick forests grow due to heavy rains.

→ These forests are so thick that the dense roof created by leaves and branches does not allow the sunlight to reach the ground.

• The ground remains dark and damp which and only shade tolerant trees may grow here.

→ Orchids, bromeliads grow as plant parasites.

• The rainforest is rich in fauna.
→ Birds such as toucans, humming birds, bird of paradise are found. 

→ Animals like monkeys, sloth and ant-eating tapirs are found here.

→ Various species of reptiles and snakes such as Crocodiles, snakes, pythons, Anaconda and boa constrictor also thrive in these jungles.

→ Several species of fishes including the flesh-eating Piranha fish is also found in the river.

People of the Rainforests

• Men hunt and fish along the rivers, women take care of the crops.

→ As hunting and fishing are uncertain it is the women who keep their families alive by feeding them the vegetables they grow.

• People practice “slash and burn agriculture”.

• The staple food is manioc, also known as cassava that grows under the ground like the potato.

→ They mainly grow tapioca, pineapple and sweet potato.

→ They also eat queen ants and egg sacs.

• Cash crops like coffee, maize and cocoa are also grown.

• The rainforests provide a lot of wood for the houses.

→ Some families live in thatched houses shaped like beehives while other large apartment-like houses called “Maloca” with a steeply slanting roof.

• Life of the people of the Amazon basin is slowly changing.

→ Amazon highway made all parts of the rainforest accessible. 

→ Aircrafts and helicopters are also used for reaching various places. 

→ The indigenous population was pushed out from the area and forced to settle in new areas where they continued to practice their distinctive way of farming.

•  The developmental activities are leading to the gradual destruction of the biologically diverse rainforests.

Life in the Ganga-Brahmapura Basin

• The tributaries of rivers Ganga and Brahmaputra together form the Ganga-Brahmaputra basin in the Indian subcontinent.

→ The basin lies in the sub-tropical region that is situated between 10°N to 30°N latitudes.

• The tributaries of the River Ganga like the Ghaghra, the Son, the Chambal, the Gandak, the Kosi and the tributaries of Brahmaputra like Dibang River, Lohit River, Teesta, Manas drain it.

• Main features of the basin: The plains of the Ganga and the Brahmaputra, the mountains and the foothills of the Himalayas and the Sundarbans delta.

Climate

• The area is dominated by monsoon climate. 

→ The monsoon brings rains from mid-June to mid-September.

• The summers are hot and the winters cool.

Topography

• The basin area has varied topography.

• The mountain areas with steep slopes have inhospitable terrain therefore, less number of people in the mountain area.

• Agriculture is the main occupation of the people in the plains because soil is fertile.

→ The density of population of the plains is very high.

• Paddy is the main crop while other crops grown are wheat, maize, sorghum, gram, millets, jute and sugarcane.

→  Cash crops like sugarcane and jute are also grown.

→ In West Bengal and Assam tea is grown. 

→ Silk is produced through the cultivation of silk worms in parts of Bihar and Assam.

→ Crops are grown on terraces in the mountains and hills.

Vegetation

• The vegetation cover of the area varies according to the type of landforms.

• In the Ganga and Brahmaputra plain tropical deciduous trees grow, along with teak, sal and peepal.

→ Thick bamboo groves are common in the Brahmaputra plain.

• In parts of Uttarakhand, Sikkim and Arunachal Pradesh, coniferous trees like pine, deodar and fir can be seen because the climate is cool and the slopes are steep.

Wildlife

• Elephants, tigers, deer and monkeys are common. 

• The one-horned rhinoceros is found in the Brahmaputra plain. 

• In the delta area, Bengal tiger, crocodiles and alligator are found.

• The most popular varieties of the fish are the rohu, catla and hilsa. 

• Fish and rice is the staple diet of the people living in the area.

Towns and Cities

• The cities of Allahabad, Kanpur, Varanasi, Lucknow, Patna and Kolkata all with the population of
more than ten lakhs are located along the River Ganga.

• The wastewater from these towns and industries is discharged into the rivers which pollute the rivers.

Transportation

• All the four ways of transport are well developed in the Ganga-Brahmaputra basin. 

→ In the plain areas the roadways and railways transport the people from one place to another. 

→ The waterways, is an effective means of transport particularly along the rivers. 

→ The plain area also has a large number of airports.

Tourism Centres

• Tourism is another important activity of the basin.

• Some important places are: Taj Mahal on the banks of River Yamuna in Agra, Buddhists stupas in Uttar Pradesh and Bihar etc.

NCERT Solutions of Chapter 8 Human Environment Interactions: The tropical and subtropical regions

Class 10 Science Lab Manual Work SA-I NCERT

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CBSE Practicals for Class 10 Science Lab Manual Work SA-I

List of Experiments to be performed for Summative Assessment -I during practical exams. The list of experiments include the practicals from Biology, Physics and Chemistry and truly based NCERT Lab books. Click on the list to get the details of the experiments for lab manual works. These laboratory manual works are prescribed by the CBSE for Class 10 Science students. Get the details to complete your lab manual practical works which is based on NCERT.

Procedure of recording of an experiment

List of apparatus used in experiment with application and diagrams

Chemistry Practicals and Lab Manual Works for Class 9 SA I

Experiment 1: To find the pH of the following samples by using pH paper/universal indicator:
    a. Dilute Hydrochloric Acid
    b. Dilute NaOH solution
    c. Dilute Ethanoic Acid solution
    d. Lemon juice
    e. Water
    f. Dilute Sodium Bicarbonate solution

Experiment 2: To study the properties of acids and bases (HCl & NaOH) by their reaction with:    a. Litmus solution (Blue/Red)
    b. Zinc metal
    c. Solid sodium carbonate

Experiment 3: To perform and observe the following reactions and classify them into:    i. Combination reaction
    ii. Decomposition reaction
    iii. Displacement reaction
    iv. Double displacement reaction
        1) Action of water on quick lime
        2) Action of heat on ferrous sulphate crystals
        3) Iron nails kept in copper sulphate solution
        4) Reaction between sodium sulphate and barium chloride solutions

Experiment 4: i) To observe the action of Zn, Fe, Cu and Al metals on the following salt solutions:    a. ZnSO₄ (aq)
b. FeSO₄ (aq)
c. CuSO₄ (aq)
d. Al2(SO₄)₃ (aq)

ii) Arrange Zn, Fe, Cu and Al (metals) in the decreasing order of reactivity based on the above result.

Physics Practicals and Lab Manual Works for Class 9 SA I

Experiment 5: To study the dependence of potential difference (V) across a resistor on the current (I) passing through it and determine its resistance. Also plot a graph between V and I.

Experiment 6: To determine the equivalent resistance of two resistors when connected in series.

Experiment 7: To determine the equivalent resistance of two resistors when connected in parallel.

Biology Practicals and Lab Manual Works for Class 9 SA I

Experiment 8: To prepare a temporary mount of a leaf peel to show stomata.

Experiment 9: To show experimentally that light is necessary for photosynthesis.

Experiment 10: To show experimentally that carbon dioxide is given out during respiration.

Notes of Ch 5 Industries| Class 8th Geography

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Study Material and Notes of Ch 5 Industries Class 8th Geography

Topics in the Chapter

• Introduction

• Classification of Industries
• Factors affecting location of Industries
• Industrial System
• Industrial Regions
• Distribution of Major Industries
• Iron and Steel Industry
→ Timeline of Iron and Steel industry's location
→ Jamshedpur
→ Why Sakchi was chosen to set up the steel plant
→ Pittsburgh
→ Why iron and steel industry developed in Pittsburgh
• Cotton Textile Industry
→ Ahmedabad
→ Why textile industry developed in Ahmedabad
→ Osaka
→ Why textile industry developed in Osaka
• Information Technology (IT)
→ Locational advantages Silicon plateau - Bangalore
→ Locational advantages of Silicon valley - California

Introduction

• Secondary activities or manufacturing change raw materials into products of more value to people.
→ Example: Pulp changed into paper and paper into a note book.

• Industry refers to an economic activity that is concerned with production of goods, extraction of minerals or the provision of services.

→ Example: Iron and steel industry (production of goods), coal mining industry (extraction of coal) and tourism industry (service provider).

Classification of Industries

• Industries can be classified on the basis:

→ Raw materials

→ Size

→ Ownership

• On the Basis of Raw Materials:

→ Agro based industries: Use plant and animal based products as their raw materials. Examples: Food processing, vegetable oil, cotton textile, dairy products and leather industries.

→ Mineral based industries: Use mineral ores as their raw materials. The products of these industries feed other industries. Example: Iron made from iron ore.

→ Marine based industries: Use products from the sea and oceans as raw materials. Examples: Industries processing sea food or manufacturing fish oil.

→ Forest based industries: Use forest produce as raw materials. Examples: pulp and paper, pharmaceuticals, furniture and buildings.

• On the Basis of Size (refers to the amount of capital invested, number of people employed and the volume of production):

→ Small Scale industries: Use lesser amount of capital and technology. Example: Cottage or household industries where the products are manufactured by hand, by the artisans. Basket weaving, pottery and other handicrafts are products of cottage industry.

→ LargeScale industries: Use higher capital is higher and superior technology. Examples: Silk weaving and food processing industries.

• On the basis of Ownership:

→ Private Sector industries: Owned and operated by individuals or a group of individuals. Examples: Reliance Industries Limited and ITC Limited.

→ Public sector industries: Owned and operated by the government. Examples: Hindustan Aeronautics Limited and Steel Authority of India Limited.

→ Joint sector industries: Owned and operated by the state and individuals or a group of individuals. Example: Maruti Udyog Limited.

→ Co-operative sector industries: Owned and operated by the producers or suppliers of raw materials, workers or both. Examples: Anand Milk
Union Limited and Sudha Dairy.

Factors affecting location of Industries

• The factors affecting the location of industries areavailability of:
→ Raw material
→ Land
→ Water
→ Labour
→ Power
→ Capital
→ Transport
→ Market

• Sometimes, the government provides incentives like subsidised power, lower transport cost and other infrastructure so that industries may be located in backward  areas.

Industrial System

• An industrial system consists of inputs, processes and outputs.

→ Inputs include raw materials, labour and costs of land, transport, power and other infrastructure.

→ The processes include a wide range of activities that convert the raw material into finished products.

→ The outputs are the end product and the income earned from it.

Industrial Regions

• When a number of industries locate close to each other and share the benefits of their closeness, they make a Industrial regions.

• Industrial regions of the world: eastern North America, western and central Europe, eastern Europe and eastern Asia.

• Industrial regions in India: Mumbai- Pune cluster, Bangalore-Tamil Nadu region, Hugli region, Ahmedabad-Baroda region, Chottanagpur industrial belt, Vishakhapatnam-Guntur belt, Gurgaon-Delhi-Meerut region and the Kollam-Thiruvanathapuram industrial cluster.

Distribution of Major Industries

• The world’s major industries are the iron and steel industry, the textile industry and the information technology industry.

• The iron and steel and textile industry are the older industries while information technology is an emerging industry.

Iron and Steel Industry

• This is a feeder industry whose products are used as raw material for other industries.

• The inputs for this industry include raw materials such as iron ore, coal and limestone, along with labour, capital, site and other infrastructure.

• The process of converting iron ore into steel involves many stages.
→ The raw material is put in the blast furnace where it undergoes smelting.
→ It is then refined.

• The output obtained is steel which may be used by other industries as raw material.

Iron and Steel

• Steel is often called the backbone of modern industry.
→ Daily use tools, Ships, trains, trucks, and autos are made largely of iron or steel.

• Features of Steel:
→ Steel is tough and it can easily be shaped, cut, or made into wire.
→ Special alloys of steel can be made by adding small amounts of other metals such as aluminium, nickel, and copper.
→ Alloys give steel unusual hardness, toughness, or ability to resist rust.

Timeline of Iron and Steel industry's location

• Before 1800 A.D. iron and steel industry was located where raw materials, power supply and running water were easily available.

• Between 1850 to 1900 A.D., the  ideal location for the industry was near coal fields and close to canals and railways.

• After 1950, iron and steel industry began to be located on large areas of flat land near sea ports because by this time steel works had become very large and iron ore had to be imported from overseas.

• Location of iron and steel industry in the world: Germany, USA, China, Japan and Russia.

• Location of iron and steel industry in India: Bhilai (Chhattisgarh), Durgapur, Burnpur (West Bengal),  Rourkela (Odisha), Bokaro, Jamshedpur (Jharkhand).

• Other important steel centres: Bhadravati and Vijay Nagar in Karnataka, Vishakhapatnam in Andhra Pradesh, Salem in Tamil Nadu.

Jamshedpur

• Before independence, Tata Iron and Steel Company Limited (TISCO) was only one iron and steel plant in the country which was privately owned.

• After Independence, the government set up several iron and steel plants.
→ TISCO was started in 1907 at Sakchi, near the confluence of the rivers Subarnarekha and Kharkai in Jharkhand. Later on, Sakchi was renamed as Jamshedpur.

Why Sakchi was chosen to set up the steel plant

• This place was only 32 km away from Kalimati station on the Bengal-Nagpur railway line.

• It was close to the iron ore, coal and manganese deposits as well as to Kolkata, which provided a large market.

• TISCO, gets coal from Jharia coalfields, and iron ore, limestone, dolomite and manganese from Odisha and Chhattisgarh.

• The Kharkai and Subarnarekha rivers ensured sufficient water supply. Government initiatives provided adequate capital for its later development.

Pittsburgh

• It is an important steel city of the United States of America. 

Why iron and steel industry developed in Pittsburgh

• The raw material such as coal is available locally, while the iron ore comes from the iron mines at Minnesota, about 1500 km from Pittsburgh. 

→ Between these mines and Pittsburgh, Great Lakes waterway is present which is one of the world’s best routes for shipping ore cheaply. 

→ Trains carry the ore from the Great Lakes to the Pittsburgh area. 

→ The Ohio, the Monogahela and Allegheny rivers provide adequate water supply.

• Today,, Large steel mills are located in the valleys of the Monogahela and Allegheny rivers above Pittsburgh and along the Ohio River below it. 

• Finished steel is transported to the market by both land and water routes.

• Other factories present in Pittsburgh area use steel as their raw material to make many different products such as railroad equipment, heavy machinery and rails.

Cotton Textile Industry

• The textile industry can be divided on the basis of raw materials i.e., fibres used in them.

• Fibres can be of two types:

→ Natural: Obtained from wool, silk, cotton, linen and jute.

→ Man-made: It includes nylon, polyester, acrylic and rayon.

• Till the industrial revolution, cotton cloth was made using hand spinning techniques (wheels) and looms. 

• In 18th century, power looms facilitated the development of cotton textile industry, first in Britain and later spread to other parts of the world.

• Important producers of cotton textiles: India, China, Japan and the USA.

• Before the British rule, Indian hand spun and hand woven cloth popular worldwide for their quality and design but the production of hand woven cotton textile was expensive and time consuming.

→ However, the traditional cotton textile industry could not face the competition from the new textile mills of the West, which produced cheap and good quality fabrics through mechanized industrial units.

• The first successful mechanized textile mill was established in Mumbai in 1854.

• Location of cotton textile industry in India:

→ Initially this industry flourished in the states of Maharashtra and Gujarat because of favourable humid climate.

→ But today, humidity can be created artificially, and raw cotton is a pure and not weight losing raw
material, so this industry has spread to other parts of the country such as Coimbatore, Kanpur, Chennai, Ahmedabad, Mumbai, Kolkata, Ludhiana, Puducherry and Panipat.

Ahmedabad

• It is located in Gujarat on the banks of the Sabarmati river.

• The first mill was established in 1859 after Mumbai.

• It soon became the second largest textile city of India, after Mumbai and was therefore often referred to as the ‘Manchester of India’.

Why textile industry developed in Ahmedabad 

• Ahmedabad is situated very close to cotton growing area which ensures easy availability of raw material. 

• The climate is ideal for spinning and weaving. 

• The flat terrain and easy availability of land is suitable for the establishment of the mills.

• The densely populated states of Gujarat and Maharashtra provide both skilled and semi-skilled

labour.

• Well developed road and railway network permits easy transportation of textiles to different parts of the country, thus providing easy access to the market.

• Mumbai port nearby facilitates import of machinery and export of cotton textiles.

• But in the recent years, Ahmedabad textile mills facing problems.

→ Several textile mills have closed down due to the emergence of new textile centres in the country as well as non-upgradation of machines and technology in the mills of Ahmedabad.

Osaka

• It is an important textile centre of Japan, also known as the ‘Manchester of Japan’.

Why textile industry developed in Osaka

• The extensive plain around Osaka ensured that land was easily available for the growth of cotton mills.

• Warm humid climate is well suited to spinning and weaving. 

• The river Yodo provides sufficient water for the mills. 

• Labour is easily available. 

• Location of port facilitates import of raw cotton and for exporting textiles.

• The textile industry at Osaka depends completely upon imported raw materials. 

→ Cotton is imported from Egypt, India, China and USA. 

• The finished product is mostly exported and has a good market due to good quality and low price.

• Recently, the cotton textile industry of Osaka has been replaced by other industries, such as iron and steel, machinery, shipbuilding, automobiles, electrical equipment and cement.

Information Technology (IT)

• The information technology industry deals in the storage, processing and distribution of information.

• This industry has become global due to a series of technological, political, and socio-economic events.

• Major hubs of the IT industry of the world: Silicon Valley, California and Bangalore, India.

• There are other emerging information technology hubs in metropolitan centres of India such as Mumbai, New Delhi, Hyderabad and Chennai. 

→ Other cities such as Gurgaon, Pune, Thiruvanthapuram, Kochi and Chandigarh re also important centres of the IT industry.

Locational advantages Silicon plateau - Bangalore

• Bangalore has the largest number of educational institutions and IT colleges in India.

• The city was considered dust free with low rents and low cost of living.

• The state government of Karnataka was the first to announce an IT Policy in 1992.

• The city has the largest and widest availability of skilled managers with work experience.

Locational advantages of Silicon valley - California

• Close to some of the most advanced scientific and technological centres in the world

• Pleasant climate with an attractive and a clean environment. 

• Plenty of space for development and future expansion.

• Located close to major roads and airports.

• Good access to markets and skilled work force.

NCERT Solutions of Chapter 5 Industries

To find the pH of the samples by using pH paper/universal indicator - Lab Work

September 28, 2016, 4:17 pm

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To find the pH of the following samples by using pH paper/universal indicator: Dilute Hydrochloric Acid, Dilute NaOH solution, Dilute Ethanoic Acid solution, Lemon juice, Water and Dilute Sodium Bicarbonate solution

Aim

To find the pH of the following samples by using pH paper/universal indicator:
a. Dilute Hydrochloric Acid
b. Dilute NaOH solution
c. Dilute Ethanoic Acid solution
d. Lemon juice
e. Water
f. Dilute Sodium Bicarbonate solution

Theory
The pH is the measure of the acidic (or basic) power of a solution. It is a scale for measuring hydrogen ion concertration in a solution. The pH scale varies from 0 to 14. At 25°C (298 K), a neutral solution has pH equal to 7. A value less than 7 on the pH scale represents an acidic solution whereas basic solution has pH value more than 7.
pH is defined as the negative logarithm(base 10) of the hydrogen ion concentration in moles per litre.
pH = -log₁₀[H⁺]

Chemicals Required
Dilute HCl, Dilute NaOH Solution, Dilute CH₃COOH solution, Fresh Lemon juice, Water and Dilute NaHCO₃ solution

Apparatus required
Test tubes, Test Tubes Stand, Dropper, Glass Rod, pH Paper strips and pH colour chart

Procedure 

Step 1: Six clean test tubes is placed in a test tube stand.
Step 2: Dilute HCl, Dilute NaOH Solution, Dilute CH₃COOH solution, Lemon juice, Water and Dilute NaHCO₃ solution are taken separately in six test tubes and labelled.
Step 3: One or two drops of each test solution on different strips of pH papers are put using a glass rod. Glass rod used for one sample must be washed with water before used for the other sample.
Step 4: Note the pH by comparing the colour appeared on the pH paper with those on colour chart for pH paper.
5. For determining the pH of lemon juice, squeeze the fruit and place 1 or 2 drop of the juice on the pH paper.

Observations

Sl. No.	Sample Solution	Colour appeared on pH paper	pH of the solution (Approximate)	Inference
1.	Dilute HCl	Red	1	Strong acid
2.	Dilute NaOH Solution	Purple	14	Strong alkali
3.	Dilute CH3COOH solution	Yellow	3	Weak acid
4.	Lemon juice	Orange	2	Acid
5.	Water	Green	7	Neutral
6.	Dilute NaHCO3 solution	Blue	9	Weak alkali

Results and Discussions
As pH depends upon H⁺ concentration and in an aqueous solution H⁺ and OH^-  ion concentrations are correlated, therefore, every acidic and basic solution shows different colour at different pH.

Precautions
1. The test sample solutions should be freshly prepared and the fruit lemon juice samples should also be fresh.
2. Glass rod used for one sample should be used for the other sample only after washing it with water.
3. Acids must be handled carefully.

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NCERT Solutions for Class 9th: पाठ 4- जलवायु भूगोल

September 29, 2016, 4:26 pm

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NCERT Solutions for Class 9th: पाठ 4-  जलवायु भूगोल (jalwaayu) Bhugol

ज्ञात कीजिए

1. राजस्थान में घरों की दीवार मोटी तथा छत चपटी क्यों होती है?

उत्तर

राजस्थान के घरों की दीवार मोटी इसलिए होती हैं ताकि वे गर्मी को घर के अंदर आने से रोकें वहीं चपटी छत रेगिस्तानी इलाके में होने वाली हल्की बारिश को संरक्षित रखने के लिए होते हैं।

2. तराई क्षेत्र तथा गोवा एवं मैंगलोर में ढाल वाली छतें क्यों होतीं हैं?

उत्तर

चूँकि तराई क्षेत्र तथा गोवा एवं मैंगलोर में ज्यादा वर्षा होती है इसलिए यहाँ ढाल वाली छतें होतीं है ताकि वर्षा का पानी जल्दी इन छतों से बह जाए।

3. असम में प्रायः कुछ घर बाँस के खम्बों (Stilt) पर क्यों बने होते हैं?

उत्तर

बाढ़ और जंगली जानवरों के खतरे से बचने के लिए असम में प्रायः कुछ घर बाँस के खम्बों पर बने होते हैं।

ज्ञात कीजिए

1. विश्व के अधिकतर मरुस्थल उपोष्ण कटिबंधीय भागों में स्थित महाद्वीपों के पश्चिमी किनारे पर क्यों स्थित है?

उत्तर

विश्व के अधिकतर मरुस्थल उपोष्ण कटिबंधीय भागों में स्थित महाद्वीपों के पश्चिमी किनारे पर स्थित इसलिए हैं क्योंकि इस क्षेत्र में चलने वाली व्यापारिक पवन अपनी नमी को पूर्वी भाग में ही निकाल देती है। ये महाद्वीपों के पश्चिमी किनारे तक पहुँचने से पहले ही सूखी हो चुकी होतीं हैं। ठंडी महासागरीय धाराएँ भी हवा को थट के ऊपर स्थिर कर देती हैं जिससे बादल निर्माण नहीं हो पाता है।

अभ्यास

पृष्ठ संख्या: 41

1. नीचे दिए गए चार विकल्पों में से सही उत्तर चुनें।

(i) नीचे दिए गए स्थानों में से किस स्थान पर विश्व में सबसे अधिक वर्षा होती है?
(क) सिलचर
(ख) चेरापूंजी
(ग) मासिनराम
(घ) गुवाहाटी
► (ग) मासिनराम

(ii) ग्रीष्म ऋतू में उत्तरी मैदानों में बहने वाली पवन को निम्नलिखित में से क्या कहा जाता है?
(क) काल वैशाखी
(ख) व्यापारिक पवनें
(ग) लू
(घ) इनमें से कोई नहीं
► (ग) लू

(iii) निम्नलिखित में से कौन-सा कारण भारत के उत्तर-पश्चिम भाग में शीत ऋतू में होने वाली वर्षा के लिए उत्तरदायी है-
(क) चक्रवातीय अवदाब
(ख) पश्चिमी विक्षोभ
(ग) मानसून की वापसी
(घ) दक्षिण-पश्चिम मानसून
► (क) चक्रवातीय अवदाब

(iv) भारत में मानसून का आगमन निम्नलिखित में से कब होता है-
(क) मई के प्रारंभ में
(ख) जून के प्रारंभ में
(ग) जुलाई के प्रारंभ में
(घ) अगस्त के प्रारंभ में
► (ख) जून के प्रारंभ में

(v) निम्नलिखित में से कौन-सी भारत में शीत ऋतू की विशेषता है-
(क) गर्म दिन व गर्म रातें
(ख) गर्म दिन व ठंडी रातें
(ग) ठंडा दिन व ठंडी रातें
(घ) ठंडा दिन व गर्म रातें
► (ख) गर्म दिन व ठंडी रातें

2. निम्न प्रश्नों के उत्तर संक्षेप में दीजिए।

(i) भारत की जलवायु को प्रभावित करने वाले कौन-कौन से कारक हैं?

उत्तर

भारत की जलवायु को प्रभावित करने वाले कारक हैं - अक्षांश, ऊँचाई और वायु, दाब एवं पवन, समुद्र से दूरी, महासागरीय धाराएँ तथा उच्चावच लक्षण।

(ii) भारत में मानसूनी प्रकार की जलवायु क्यों है?

उत्तर

भारत में मानसूनी प्रकार की जलवायु है क्योंकि भारत की जलवायु मानसून पवनों के प्रभाव क्षेत्र के अंतर्गत आता है जो 20° उत्तर से लेकर 20° दक्षिण तक सीमित हैं।

(iii) भारत के किस भाग में दैनिक तापमान अधिक होता है और क्यों?

उत्तर

भारतीय मरुस्थल जो भारत के उत्तर-पश्चिम भाग में अवस्थित है में दैनिक तापमान अधिक होता है क्योंकि वहाँ रेत पायी जाती है जो दिन के समय सूरज की रोशनी में बहुत जल्दी गर्म हो जाती है।

(iv) किन पवनों के कारण मालबार तट पर वर्षा होती है?

उत्तर

दक्षिण-पश्चिम पवनों के कारण मालबार तट पर वर्षा होती है।

(vi) जेट धाराएँ क्या हैं तथा वे किस प्रकार भारत की जलवायु को प्रभावित करती हैं?

उत्तर

जेट धाराएँ पश्चिमी तेज गति की पवनें हैं जो संकरी क्षेत्र में स्थित क्षोभमंडल में बहती हैं। ये लगभग 27° से 30° उत्तर अक्षांशों के स्थित होती हैं, इसलिए इन्हें उपोष्ण कटिबंधीय पश्चिमी जेट धाराएँ कहा जाता है।
भारत में, ये जेट धाराएँ ग्रीष्म ऋतू को छोड़कर पुरे वर्ष हिमालय के दक्षिण में प्रवाहित होती हैं। यह पश्चिमी प्रवाह पश्चिमी विक्षोभ के लिए जिम्मेदार हैं जो देश के उत्तर और उत्तर-पश्चिमी भागों में अनुभव की जाती हैं।

(vii) मानसून को परिभाषित करें। मानसून में विराम से आप क्या समझते हैं?

उत्तर

वायु की दिशा के मौसमी परिवर्तन को मानसून कहा जाता है। मानसून में विराम में एक परिघटना है जिसमें मानसूनी वर्षा एक समय में कुछ दिनों तक ही होती है। इनमें वर्षा रहित अंतराल भी होते हैं। ये विराम मानसूनी गर्त की गति से संबंधित होते हैं।

(viii) मानसून को एक सूत्र में बाँधने वाला क्यों समझा जाता है?

उत्तर

निम्नलिखित कारणों से मानसून को एक सूत्र में बाँधने वाला समझा जाता है -
• सम्पूर्ण भारतीय भूदृश्य, इसके वनस्पति और जीव, आदि मानसून से प्रभावित हैं।

• ये मानसूनी हवाएँ कृषि गतिविधियों के लिए पानी उपलब्ध कराकर पूरे देश को एक सूत्र में बाँधती है।

• कृषि चक्र से संबंधित त्यौहार विभिन्न हिस्सों में अलग-अलग नामों से जाने जाते हैं लेकिन उनके उत्सव का समय मानसून तय करता है।

• साल दर साल, उत्तर दक्षिण और पूर्व से पश्चिम के भारत के लोग बेसब्री से मानसून के आने का इंतजार करते हैं।

• नदी घाटीयाँ जो मानसून वर्षा का पानी ले जातीं हैं वो भी एक ही नदी घाटी इकाई के रूप में एकजुट हो जातीं हैं।

3. उत्तर-भारत में पूर्व से पश्चिम की ओर वर्षा की मात्रा क्यों घटती जाती है?

उत्तर

दक्षिणी-पश्चिमी मानसून की बंगाल की खाड़ी शाखा अत्यधिक मात्रा में नमी लिए हुए उत्तर-पूर्व की ओर जाती है और इस क्षेत्र में भारी वर्षा लाती है। जैसे-जैसे वे पश्चिम की ओर आगे बढ़ते हैं, उनकी नमी घटती जाती है जिससे पश्चिम की ओर वर्षा की मात्रा घटती जाती है।

4. कारण बताएँ-

(i) भारतीय उपमहाद्वीप में वायु की दिशा में मौसमी परिवर्तन क्यों होता है?

उत्तर

वायु की दिशा में मौसमी परिवर्तन भारतीय उपमहाद्वीप में वायु दाब में अंतर के कारण होता है। भारतीय उपमहाद्वीप में वायु की दिशा में मौसमी परिवर्तन लाने में एलनीनो प्रमुख भूमिका निभाता है।

(ii) भारत में अधिकतर वर्षा कुछ ही महीनों में होती है।

उत्तर

मानसून जून के पहले सप्ताह से शुरू होती है और काफी तीव्र प्रगति कर मध्य जुलाई तक लगभग पूरे देश तक पहुँच जाती हैं। इसलिए, भारत में अधिकतर वर्षा कुछ ही महीनों में होती है; मुख्य रूप से अगस्त से जून के महीने में।

(iii) तमिलनाडु तट पर शीत ऋतू में वर्षा होती है।

उत्तर

निम्न दाब वाली अवस्था बंगाल की खाड़ी पर स्थानांतरित होने के कारण तमिलनाडु तट पर शीत ऋतू में वर्षा होती है।

(iv) पूर्वी तट के डेल्टा वाले क्षेत्र में प्रायः चक्रवात आते हैं।

उत्तर

बंगाल की खाड़ी विभिन्न दाब परिवर्तन का केंद्र है इसलिए वहाँ हमेशा चक्रवात के विकास का एक मौका है। इस कारण, पूर्वी तट के डेल्टा वाले क्षेत्र में प्रायः चक्रवात आते हैं।

(v) राजस्थान, गुजरात के कुछ भाग तथा पश्चिमी घाट का वृष्टि छाया सूखा प्रभावित क्षेत्र है।

उत्तर

कुछ भाग अरावली की बारिश छाया क्षेत्र में आते है इसलिए, वे सूखा प्रभावित क्षेत्र हैं क्योंकि वहाँ बारिश बहुत कम होती है।

5. भारत की जलवायु अवस्थाओं की क्षेत्रीय विभिन्नताओं को उदाहरण सहित समझाएँ।

उत्तर

भारत की जलवायु परिस्थितियों में क्षेत्रीय भिन्नता है। तापमान और वर्षन एक स्थान से दूसरे स्थान पर तथा एक मौसम से दूसरे मौसम में भिन्न हैं।

• गर्मियों में, राजस्थान के मरुस्थल में कुछ स्थानों का तापमान लगभग 50° सेल्सियस तक पहुँच जाता है, जबकि जम्मू-कश्मीर के पहलगाम में तापमान लगभग 20° सेल्सियस रहता है।

• सर्दी की रात में, जम्मू-कश्मीर में द्रास का तापमान -45° सेल्सियस तक हो सकता है, जबकि थिरुवनंथपुरम् में यह 22° सेल्सियस हो सकता है।

• केरल या अंडमान एवं निकोबार में दिन तथा रात का तापमान लगभग समान ही रहता है।

• सामान्य रूप से तटीय क्षेत्रों के तापमान में अंतर कम होता है तथा देश के आंतरिक भागों में मौसमी या ऋतूनिष्ठ अंतर अधिक होता है।

• उत्तरी मैदान में वर्षा की मात्रा सामान्यतः पूर्व से पश्चिम की ओर घटती जाती है।

• देश के अधिकतर भागों में जून से सितंबर तक वर्षा होती है, लेकिन कुछ क्षेत्रों जैसे तमिलनाडु तट पर अधिकतर वर्षा अक्टूबर एवं नवंबर में होती है।

6. मानसून अभिक्रिया की व्याख्या करें।

उत्तर

निम्नलिखित कारक मानसून की अभिक्रिया के लिए जिम्मेदार हैं:

• स्थल तथा जल के गर्म एवं ठंडे होने की विभ्रेदी प्रक्रिया के कारण भारत के स्थल भाग पर निम्न दाब का क्षेत्र उतपन्न होता है, जबकि इसके आसपास के समुद्रों के ऊपर उच्च दाब का क्षेत्र बनता है।

• अंतः उष्ण कटिबंधीय अभिसरण क्षेत्र प्रायः विषुवत् वृत्त से 5° उत्तर में स्थिति होता है। ग्रीष्म ऋतू के दिनों में अंतः उष्ण कटिबंधीय अभिसरण क्षेत्र की स्थिति गंगा के मैदान की ओर खिसक जाती है। इसे मानसून ऋतू में में मानसून गर्त के नाम से भी जाना जाता है।

• हिन्द महासागर में मेडागास्कर के पूर्व लगभग 20° दक्षिण अक्षांश के ऊपर उच्च दाब वाल क्षेत्र होता है। इस उच्च दाब वाले क्षेत्र की स्थिति एवं तीव्रता भारतीय मानसून को प्रभावित करती है।

• ग्रीष्म ऋतू में, तिब्बत का पठार बहुत अधिक गर्म हो जाता है, जिसके परिमाणस्वरूप पठार के ऊपर समुद्र तल से लगभग 9 किलोमीटर की ऊँचाई पर तीव्र ऊर्ध्वाधर वायु धाराओं एवं उच्च दाब का निर्माण होता है।

• ग्रीष्म ऋतू में हिमालय के उत्तर-पश्चिमी जेट धाराओं का तथा भारतीय प्रायद्वीप के ऊपर उष्ण कटिबंधीय पूर्वी जेट धाराओं का प्रभाव होता है।

• दाब की अवस्था में नियतकालिक परिवर्तन को दक्षिणी दोलन के नाम से जाना जाता है।

• डार्विन, उत्तरी आस्ट्रेलिया (हिन्द महासागर 12°30' दक्षिण/131° पूर्व) तथा ताहिती (प्रशांत महासागर 18° दक्षिण/149° पश्चिम) के दाब के अंतर की गणना मानसून की तीव्रता के पूर्वानुमान के लिए की जाती है। अगर दाब का अंतर ऋणात्मक है तो इसका अर्थ होगा औसत से कम तथा विलंब से आने वाला मानसून।

7. शीत ऋतू की अवस्था एवं उसकी विशेषताएँ बताएँ।

उत्तर

शीत ऋतू की अवस्था एवं उसकी विशेषताएँ निम्नलिखित हैं:

• उत्तरी भारत में शीत ऋतू मध्य नवंबर से आरम्भ होकर फरवरी तक रहती है।

• भारत के उत्तरी भाग में दिसंबर एवं जनवरी सबसे ठंडे महीने होते हैं।

• तापमान दक्षिण से उत्तर की ओर बढ़ने पर घटता जाता है। पूर्वी तठ पर चेन्नई का औसत तापमान 24° सेल्सियस से 25° सेल्सियस के बीच होता है, जबकि उत्तरी मैदान में यह 10° सेल्सियस से 15° सेल्सियस के बीच होता है।

• दिन गर्म तथा रातें ठंडी होती हैं।

• उत्तर में तुषरापात सामान्य है तथा हिमालय के ऊपरी ढालों पर हिमपात होता है।

• देश में उत्तरी-पूर्वी व्यापारिक पवनें प्रवाहित होती हैं। चूँकि, ये पवनें स्थल से समुद्र की ओर बहती हैं तथा इसलिए देश के अधिकतर भाग में शुष्क मौसम होता है।

• सामन्यतः इस मौसम में आसमान साफ, तापमान तथा आद्रता कम एवं पवनें शिथिल तथा परिवर्तित होती हैं।

• शीत ऋतू में उत्तरी मैदानों में पश्चिम एवं उत्तर-पश्चिम से चक्रवाती विक्षोभ का अंतर्वाह विशेष लक्षण है।

• कम दाब वाली प्रणाली भूमध्यसागर एवं पश्चिमी एशिया के ऊपर उत्पन्न होती है तथा पश्चिमी पवनों के साथ भारत में प्रवेश करती है। इसके कारण शीतकाल में मैदान में वर्षा होती है तथा पर्वतों पर हिमपात होता है।
• यद्यपि शीतकाल में वर्षा कम होती है, लेकिन ये रबी फसलों के लिए बहुत महत्वपूर्ण होती है। स्थानीय तौर पर इस वर्षा को 'महावट' कहा जाता है।
• प्रायद्वीपीय भागों में समुद्री प्रभावों के कारण शीत ऋतू स्पष्ट नहीं होती।

8. भारत में होने वाली मानसूनी वर्षा एवं उसकी विशेषताएँ बताएँ।

उत्तर

मानसून की विशेषताएँ -
• मानसून का समय जून के आरंभ से लेकर मध्य सितंबर तक, 100 से 120 दिनों के बीच होता है।
• इसके आगमन के समय सामान्य वर्षा में अचानक वृद्धि हो जाती है तथा लगातार कई दिनों तक यह जारी रहती है। इसे मानसून प्रस्फोट (फूटना) कहते हैं।
• सामान्यतः जून के प्रथम सप्ताह में मानसून भारतीय प्रायद्वीप के दक्षिणी छोर से प्रवेश करता है जो बाद में दो भागों में बँट जाता है - अरब सागर शाखा और बंगाल की खाड़ी शाखा।
• देश भर में वर्षा का असमान वितरण होता है।

मानसूनी वर्षा के प्रभाव -
• भारत में कृषि काफी हद तक पानी के लिए भारतीय मानसून पर निर्भर रहता है। देर से, कम या अत्यधिक बारिश फसलों पर एक नकारात्मक प्रभाव डालता है।

• देश भर में वर्षा के असमान वितरण के कारण कुछ स्थान सूखा प्रभावित रहते हैं तो कुछ बाढ़ प्रभावित।

• मानसून भारत को एक विविध जलवायु स्वरूप प्रदान करता है जिस कारण महान क्षेत्रीय रूपों की उपस्थिति के बावजूद, यह देश और लोगों के लिए यह एकता का परिचारक है।

मानचित्र कौशल

भारत के रेखा मानचित्र पर निम्नलिखित को दर्शाएँ -

(i) 400 सेंटीमीटर से अधिक वर्षा वाले क्षेत्र

(ii) 20 सेंटीमीटर से कम वर्षा वाले क्षेत्र

(iii) भारत में दक्षिण-पश्चिम मानसून की दिशा

उत्तर

पाठ में वापिस जाएँ

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To study the properties of acid (HCl) by its reaction - Lab Work

September 30, 2016, 4:52 pm

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To study the properties of acid (HCl) by its reaction with Litmus solution (Blue/Red), Zinc metal and Solid sodium carbonate

Aim

To study the properties of  HCl by its reaction with:
a. Litmus solution (Blue/Red)
b. Zinc metal
c. Solid sodium carbonate

Theory
Acids are compounds that contain hydrogen and which dissolve in water to produce hydrogen ions (H⁺). Ions are particles that have an electrical charge. The hydrogen ions give acids their special properties but they only exist in solution, so an acid only displays its properties when it is dissolved in water. For example, HCI + aq → 4H⁺ (aq) + Cl^- (aq) The more H⁺ ions are in a solution, the more acidic it will be.
• HCl is an acid which turns blue litmus red
• HCl reacts with zinc metal to form zinc chloride and hydrogen
• HCl reacts with solid sodium carbonate to release CO₂ gas
   Na₂CO₃ (s) + 2HCl (aq) → 2NaCl + H₂O+ CO₂

Chemicals Required
Hydrochloric acid, Litmus solution (Blue and Red), Zinc metal, Sodium carbonate, Sodium hydroxide, 

Apparatus Required
Test tubes, Test tube stand and Dropper

Procedure and Observations Table

Sl. No.	Procedure	Observation	Inference
1.	Test with Litmus Solution (a) A little amount of blue litmus solutions is taken in a test tube and few drops of HCl is added to it using a dropper. (b) A little amount of red litmus solutions is taken in a test tube and few drops of HCl is added to it using a dropper.	(a) Blue litmus turns red. (b) No changes in the colour of red litmus.	HCl is an acid having pH value below 7.
2.	Reaction with Zn metal A clean and dry test tube is taken and zinc metal is added to it and placed it on test tube stand. Few drops of HCl is added on Zn pieces with the help of dropper.	A gas is evolved which burns with popping sound when a matchstick is brought near the mouth of the test tube.	The gas evolved is hydrogen. Zn(s) + HCl(aq) → ZnCl2 + H2
3.	Reaction with Na2CO3 A small quantity of solid sodium carbonate is taken in a flask and distilled water is added into it. The flask is corked with a double bore cork and a thistle funnel is inserted into the flask. Then a beaker containing lime water near the flask is placed. Then one end of the delivery tube is inserted into the flask and the other end into the beaker. HCl is added into the flask through the thistle funnel and the change in colour of the lime water is observed.	A gas is evolved which turns lime water milky.	The gas produced is carbon dioxide which gives brisk effervescence. Na2CO3(s) + 2HCl(aq) → 2NaCl + H2O+ CO2

Discussions
1. Hydrochloric acid turns blue litmus paper to red and shows no effect with red litmus solution.
2. Hydrochloric acid gives hydrogen gas when a piece of zinc is dipped in it.
3. Hydrochloric acid gives carbon dioxide gas with sodium carbonate.

Precautions
1. Hydrochloric acid should be handled with care because it can bum skin and clothes.
2. Only small quantity of chemicals should be used.
3. Hands should be cleaned properly after completing the experiments.
4. All the observations should be noted carefully.

Go to List of Experiments

कल्लू कुम्हार की उनाकोटी - पठन सामग्री और सार NCERT Class 9th Hindi

October 1, 2016, 5:19 pm

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पठन सामग्री, अतिरिक्त प्रश्न और उत्तर और सार - कल्लू कुम्हार की उनाकोटी संचयन भाग - 1

सार

इस पाठ में लेखक ने अपनी त्रिपुरा यात्रा का वर्णन किया है। इन्होनें त्रिपुरा के व्यक्तियों, धर्मों, दर्शनीय स्थलों आदि का वर्णन किया है। यह पाठ हमें छोटे से राज्य त्रिपुरा के बारे में कई जानकरियाँ देता है।

लेखक सूर्योदय के समय उठतें हैं, चाय और अखबार लेकर सुबह का आनंद लेते हैं। एक दिन लेखक की नींद बिजलियाँ चमकने और बादलों के गर्जना की कानफोड़ू आवाज़ से खुली। इस दृश्य ने उन्हें दिसम्बर 1999 की घटना जब वह 'ऑन द रोड' शीर्षक की टीवी श्रृंखला बनाने के सिलसिले में त्रिपुरा की राजधानी अगरतला की यात्रा पर गए थे की याद दिला दी। श्रृंखला का मुख्य उद्देश्य त्रिपुरा की राष्ट्रीय राजमार्ग-44 से यात्रा करने और राज्य के विकास संबंधी गतिविधियों की बारे में जानकारी देना था।

त्रिपुरा राज्य की जनसंख्या 34 प्रतिशत है, जो काफी ऊँची है। यह राज्य बांग्लादेश से तीन तरफ से घिरा है और एक तरफ से भारत के दो राज्य मिजोरम और असम सटे हैं। सोनुपुरा, बेलोनिया, सबरूम , कैलासशहर त्रिपुरा के महत्वपूर्ण शहर हैं, जो बांग्लादेश करीब है। अगरतला भी सीमा चौकी से दो किलोमीटर दूर है। बांग्लादेश, अस्मा, पश्चिम बंगाल के क्षेत्रों से लोगों की भारी आवक ने यहाँ के जनसंख्या को असंतुलित कर दिया है, जो त्रिपुरा में आदिवासी असंतोष की मुख्य वजह है।

पहले तीन दिनों में लेखक ने अगरतला और उसके नजदीक स्थित जगहों की शूटिंग की। उज्जयंत महल अगरतला का मुख्य महल है जिसमें अब वहाँ की राज्य विधानसभा बैठती है। त्रिपुरा में बाहरी लोगों के आने से समस्याएँ पैदा हुईं हैं, लेकिन इस कारण यह राज्य बहुधार्मिक समाज का उदाहरण भी बना है। त्रिपुरा में उन्नीस अनुसूचित जनजातियों और विश्व के चार बड़े धर्मों का प्रतिनिधित्व मौजूद है।

अगरतल्ला के बाद लेखक टीलियामुरा कस्बा पहुँचे जो एक विशाल गाँव है। यहाँ लेखक की मुलाकात हेमंत कुमार जमातिया से हुई। जिन्हें 1996 में संगीत नाटक अकादमी द्वारा पुरस्कृत किया जा चुका है। ये कोकबारोक बोली में गाते हैं जो त्रिपुरा की कबीलाई बोलियों में से है। हेमंत ने हथियारबंद संघर्ष का रास्ता छोड़कर चुनाव लड़ा और जिला परिषद के सदस्य बने गए थे। जिला परिषद ने लेखक के शूटिंग यूनिट के लिए एक भोज का आयोजन भी किया जिसमें उन्हें सीधा-सादा खाना परोसा गया। भोज के बाद लेखक ने हेमंत से गीत सुनाने के अनुरोध किया और उन्होंने लेखक को धरती पर बहती शक्तिशाली नदियों, ताज़गी भरी हवाओं और शांति का एक गीत गाया। बॉलीवुड के सबसे मौलिक संगीतकारों में एक एस. डी. बर्मन त्रिपुरा से ही थे।

टीलियामुरा शहर के वार्ड नं. 3 में लेखक की मुलाकात एक और गायक मंजू ऋषिदास से हुई। ऋषिदास मोचियों के एक समुदाय का नाम है जो जूते बनाने के अलावा तबला और ढोल जैसे वाद्यों का निमाण भी करते हैं। ऋषिदास रेडियो कलाकार होने के अतिरिक्त नगर पंचायत में अपने वार्ड का प्रतिनिधित्व भी करती थीं। उन्होंने लेखक को दो गीत सुनाए  जिनका लेखक ने शूटिंग किया।

टीलियामुरा के बाद त्रिपुरा का हिंसाग्रस्त इलाका शुरू होता है। लेखक वहाँ से सी.आर.पी.एफ. की हथियारबन्द गाड़ी में मनु कस्बे ओर चल पड़े। मनु कस्बा मनु नदी के किनारे स्थित है। शाम के समय वे लोग मनु कस्बा पहुँचे। वे लोग उत्तरी त्रिपुरा जिले में पहुँच चुके थे। वहाँ लोकप्रिय घरेलू गतिविधियों में से एक है अगरबत्तियों के लिए बाँस की पतली सींके तैयार करना। अगरबत्तियाँ बनाने के लिए इन्हें कर्नाटक और गुजरात भेजा जाता है।

उत्तरी त्रिपुरा जिले का मुख्यालय कैलासशहर है जो बांग्लादेश की सीमा से करीब है। यहाँ के जिलाधिकारी से लेखक ने टी.पी.एस (टरु पोटेटो सीड्स) के बारे में जाना जो मात्र 100 ग्राम में ही एक हेक्टेयर की बुआई कर देती है।

लेखक को बाद में उनकोटि के बारे में पता चला जो देश के सबसे बड़े तीर्थों में से एक है। उनाकोटी का अर्थ होता है एक करोड़ से कम। दंतकथा के अनुसार उनकोटि में शिव की एक करोड़ में से एक मूर्ति कम है। विद्वानों के अनुसार यह जगह दस वर्ग से किलोमीटर इलाके से ज्यादा में फैली हुयी है। पहाड़ों को अंदर से काटकर मूर्तियों का निर्माण किया गया है। एक विशाल चट्टान पर गंगा अवतरण की कथा को चित्रित किया गया है।

इन आधार-मूर्तियों का निर्माता कौन है यह नहीं पता है। आदिवासियों के अनुसार इन मूर्तियों का निर्माता कल्लू कुम्हार था। कल्लू पार्वती का बड़ा भक्त था और शिव-पार्वती के साथ कैलाश जाना चाहता था। पार्वती के जोर देने पर शिव कल्लू को ले जाने के लिए तैयार हो गए परन्तु उन्होंने शर्त रखी कि एक रात में कल्लू कुम्हार को शिव की एक कोटि मूर्तियाँ बनानी होंगी। कल्लू रात भर काम करता रहा परन्तु सुबह में उसकी मूर्तियों की संख्या एक करोड़ में से एक कम निकलीं। इसी बात का बहाना बनाते हुए शिव ने कल्लू कुम्हार से अपना पीछा छुड़ा लिया और कैलाश चले गए।

इस जगह की शूटिंग करते हुए लेखक को चार बजे गए। उनाकोटी में अँधेरा छा गया और बादल गरज-गरज कर बरसने लगे। आज का गर्जन ने लेखक को तीन साल पहले वाले उनाकोटी के गर्जन का याद दिला दिया।

शब्दार्थ

• अलसायी - आलस से भरी
• सोहबत - संगति
• ऊर्जादायी - शक्ति देने वाली
• खलल - बाधा
• कानफाड़ू - कानों को फाड़ने वाला
• शुक्र - मेहरबानी
• विक्षिप्तों - पागलों
• तड़ित - बिजली
• अल्लसुबह - बिलकुल सुबह
• मुहैया - उपलब्ध
• आवक - आगमन
• इर्द-गिर्द - आस-पास
• खासी - बहुत
• हस्तांतरण - एक व्यक्ति के हाथ से दूसरे के हाथ में जाना
• प्रतीकित - अभिव्यक्त करना
• मुँहजोर - मुँहफट
• आश्वस्त - विश्वाश से पूर्ण
• इरादतन - सोच-विचार कर

View NCERT Solutions of कल्लू कुम्हार की उनाकोटी

संचयन के अन्य पाठों के पठन सामग्री और सार

To study the properties of base (NaOH) by its reaction - Lab Work

October 2, 2016, 5:37 pm

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To study the properties of base (NaOH) by its reaction with Litmus solution (Blue/Red), Zinc metal and Solid sodium carbonate

Aim

To study the properties of NaOH by its reaction with:
a. Litmus solution (Blue/Red)
b. Zinc metal
c. Solid sodium carbonate

Theory
Acids are compounds that contain hydroxyl group which dissolve in water to produce hydroxyl ions (OH^-). Ions are particles that have an electrical charge.
For example, NaOH (aq) → Na⁺ (aq) + OH^- (aq) The more OH^- ions are in a solution, the more basic it will be.
• NaOH is a base which turns red litmus blue.
• NaOH reacts with zinc metal to form sodium zincate and hydrogen.
• NaOH doesn't react with solid sodium carbonate but form alkaline solution.

Chemicals Required
Sodium Hydroxide, Phenolphthalein, Litmus solution (Blue and Red), Zinc metal, Sodium carbonate, Sodium hydroxide, 

Apparatus Required
Test tubes, Test tube stand, Bunsen Burner, Matchstick and Dropper

Procedure and Observations Table

Sl. No.	Procedure	Observation	Inference
1.	Test with Litmus Solution (a) A little amount of red litmus solutions is taken in a test tube and few drops of NaOH is added to it using a dropper. (b) A little amount of blue litmus solutions is taken in a test tube and few drops of HCl is added to it using a dropper.	(a) Red litmus turns blue. (b) No changes in the colour of blue litmus.	NaOH is an alkali having pH value more than 7.
2.	Reaction with Zn metal Some pieces of zinc metal in a boiling tube is taken. Few drops of NaOH is added into the boiling tube using a dropper. Then a dropper with a fine jet on the mouth of the tube is placed. The boiling tube is heated. A burning matchstick near the mouth of the fine jet is brought.	A gas is evolved which burns with popping sound when a matchstick is brought near the mouth of the test tube.	The gas evolved is hydrogen. Zn(s) + 2NaOH(aq) → Na2ZnO2 + H2
3.	Reaction with Na2CO3 A small quantity of solid sodium carbonate in a test tube is taken and a little amount of NaOH solution is added into it. The test tube is shaken well. Few drops of phenolphthalein is added into the test tube.	The solution in the test tube turns pink.	Both NaOH and Na2CO3 are alkali so they do not react but form alkaline solution. Phenolphthalein gives pink colour in an alkaline medium.

Discussions
1. Sodium Hydroxide turns red litmus paper to blue and shows no effect with blue litmus solution.
2. Sodium Hydroxide gives hydrogen gas when a piece of zinc is dipped in it.
3. Sodium Hydroxide does not react with solid sodium carbonate.

Precautions
1. Take small quantities of zinc, HCl and NaOH for their reaction, otherwise large amount of hydrogen produced may cause explosion.
2. For hydrogen burning take a fine jet.
3. Add HCl to Na₂CO₃, only when apparatus is made carefully airtight.
3. NaOH and HCl are injurious, handle these chemicals carefully.

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To perform Action of water on quick lime and classify it - Lab Work

October 3, 2016, 5:49 pm

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To perform Action of water on quick lime and classify it on Combination reaction, Decomposition reaction, Displacement reaction and Double displacement reaction

Aim

To perform Action of water on quick lime and classify it on:
i. Combination reaction
ii. Decomposition reaction
iii. Displacement reaction
iv. Double displacement reaction

Theory
(a) When water is added slowly to a beaker containing a small amount of CaO the beaker becomes hot.
Reaction:      CaO (s)        +         H₂O (l)   →   Ca(OH)₂ (aq) + heat
      Calcium oxide(Quicklime)     Water     Calcium hydroxide(Slaked lime)
(b) In this reaction two compounds CaO and H₂O combine to give Ca(OH)₂, a single product which is an example of combination reaction. Hence it may be stated that when two or more substance(s) combine to form a single product, the reaction is called combination reaction.
(c) It has been observed that a large amount of heat is evolved in course of reaction, such type of reactions are termed as exothermic reaction.

Chemicals Required
Calcium oxide, Water

Apparatus Required
Beaker

Procedure

Step 1: A small quantity of calcium oxide (quick lime) is taken in a beaker.
Step 2: Water is slowly added to the quick lime taken in the beaker. Enough water is poured so that the quick lime remains submerged in the water.
Step 3: Beaker is touched with fingers to note the temperature.
Step 4: The beaker is left undisturbed for some time.

Observation
1. When water is added to quick lime, a suspension of slaked lime is formed.
2. The beaker was hot when it was touched with fingers.
3. A clear solution appears when the suspension of slaked lime settles down to the bottom of the beaker.

Inference
1. the reaction is highly exothermic because quick lime reacts vigorously with water to form slaked lime releasing large amount of heat .
2. Slaked lime is only slightly soluble in water, so it forms a suspension of slaked lime in water.
3. The clear solution obtained after the suspension settles is called lime water.
4. Calcium oxide and water react to form only a single product, calcium hydroxide. So the reaction is a combination reaction.

Precautions
1. Never put quick lime in water. It may cause the lime water to splash out of the container and damage eyes or skin.
2. Always take quick lime in small quantity in a beaker and then slowly pour water on it.
3. Do not add excessive water as it may cause an explosion due to vigorous reaction.
4. Do not touch or dip your fingers in lime water. Calcium hydroxide may burn the skin.

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मेरा छोटा सा निजी पुस्तकालय - पठन सामग्री और सार NCERT Class 9th Hindi

October 5, 2016, 1:07 am

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पठन सामग्री, अतिरिक्त प्रश्न और उत्तर और सार - मेरा छोटा सा निजी पुस्तकालय संचयन भाग - 1

सार

यह पाठ लेखक 'धर्मवीर भारती' की आत्मकथा है। सन् 1989 में लेखक को लगातार तीन हार्ट अटैक आए। उनकी नब्ज़, साँसें, धड़कन सब बंद हो चुकी थीं। डॉक्टरों ने उन्हें मृत घोषित कर दिया परन्तु डॉक्टर बोर्जेस ने हिम्मत नहीं हारी और उनके मृत पड़ चुके शरीर को नौ सौ वॉल्ट्स के शॉक दिए जिससे उनके प्राण तो लौटे परन्तु हार्ट का चालीस प्रतिशत हिस्सा नष्ट हो गया और उसमें में भी तीन अवरोध थे। तय हुआ कि उनका ऑपरेशन बाद में किया जाएगा। उन्हें घर लाया गया। लेखक की जिद पर उन्हें उनकी किताबों वाले कमरे में लिटाया गया। उनका चलना, बोलना, पढ़ना सब बन्द हो गया।

लेखक को सामने रखीं किताबें देखकर ऐसा लगता मानो उनके प्राण किताबों में ही बसें हों। उन किताबों को लेखक ने पिछले चालीस-पचास सालों में जमा किया था जो अब एक पुस्तकालय का रूप ले चुका था। 

उस समय आर्य समाज का सुधारवादी पुरे ज़ोर पर था। लेखक के पिता आर्यसमाज रानीमंडी के प्रधान थे और माँ ने स्त्री-शिक्षा के लिए आदर्श कन्या पाठशाला की स्थापना की थी। पिता की अच्छी खासी नौकरी थी लेकिन लेखक के जन्म से पहले उन्होंने सरकारी नौकरी छोड़ दी थी। लेखक के घर में नियमित पत्र-पत्रिकाएँ आतीं थीं जैसे 'आर्यमित्र साप्ताहिक', 'वेदोदम','सरस्वती','गृहिणी'। उनके लिए 'बालसखा' और 'चमचम' दो बाल पत्रिकाएँ भी आतीं थीं जिन्हें पढ़ना लेखक को बहुत अच्छा लगता था। लेखक बाल पत्रिकाओं के अलावा 'सरस्वती' और 'आर्यमित्र' भी पढ़ने की कोशिश करते। लेखक को 'सत्यार्थ प्रकाश' पढ़ना बहुत पसंद था। वे पाठ्यक्रम की किताबों से अधिक इन्हीं किताबों और पत्रिकाओं को पढ़ते थे।

लेखक के पिता नहीं चाहते थे की लेखक बुरे संगति में पड़े इसलिए उन्हें स्कूल नहीं भेजा गया और शुरू की पढाई के लिए घर पर मास्टर रखे गए। तीसरी कक्षा में उनका दाखिला स्कूल में करवाया गया। उस दिन शाम को पिता लेखक को घुमाने ले गए और उनसे वादा करवाया कि वह पाठ्यक्रम की पुस्तकें भी ध्यान से पढेंगे। पांचवीं में लेखक फर्स्ट आये और अंग्रेजी में उन्हें सबसे ज्यादा नंबर आया। इस कारण उन्हें स्कूल से दो किताबें इनाम में मिलीं। एक किताब में लेखक को विभिन्न पक्षियों के बारे में जानकारी मिली तथा दूसरे पानी की जहाजों की जानकारी मिली। लेखक के पिता ने अलमारी के खाने से अपनी चीज़ें हटाकर जगह बनाई और बोले 'यह अब तुम्हारी लाइब्रेरी। यहीं से लेखक की निजी लाइब्रेरी की शुरुआत हुई।

लेखक के मुहल्ले में एक लाइब्रेरी थी जिसमें लेखक बैठकर किताबें पढ़ते थे उन्हें साहित्यिक किताबें पढ़ने में बहुत आनंद आता। उन दिनों विश्व साहित्य के किताबों के हिंदी में खूब अनुवाद हो रहे थे जिससे लेखक को विश्व का भी अनुभव होता था। चूँकि लेखक के पिता की मृत्यु हो चुकी थी इसलिए वे किताबें घर नही ले जा पाते थे जिसका उन्हें बहुत दुःख होता था। लेखक का आर्थिक संकट बहुत बढ़ गया था। वे अपने प्रमुख पाठ्यक्रम की पुस्तकें भी सेकंड-हैंड ही लेते थे और बाकी के पुस्तकों का सहपाठियों से लेकर नोट्स बनाते थे।

लेखक ने किस तरह से अपनी पहली साहित्यिक पुस्तक खरीदी उसका वर्णन किया है। उन्होंने उस साल इंटरमीडिएट पास किया था और अपनी पुरानी पाठ्यपुस्तकें बेचकर बी.ए की पुस्तकें लेने सेकंड-हैण्ड पुस्तकों की दूकान पर खड़े थे। पाठ्यपुस्तकें खरीद कर लेखक के पास दो रूपए बचे। सामने के सिनेमाघर में 'देवदास' लगी थी। लेखक उस फिल्म के एक गाना हमेशा गुनगुनाते रहते थे जिसे सुनकर एक दिन माँ ने कहा 'जा फिल्म देख आ।' लेखक बचे दो रूपए लेकर सिनेमा घर गए। फिल्म शुरू होने में देरी थी। लेखक सामने एक परिचित की पुस्तकों की दूकान के सामने चक्कर लगाने लगे। तभी वहाँ उन्हें 'देवदास' की पुस्तक दिखाई दी। लेखक ने उस पुस्तक को ले लिया चूँकि पुस्तक की कीमत केवल दस आने थी जबकि फिल्म देखने में डेढ़ रूपए लगते हुए। बचे हुए पैसे लेखक ने माँ को दे दिए। यह उनकी निजी लाइब्रेरी की पहली किताब थी।

आज लेखक के लाइब्रेरी में उपन्यास, नाटक, कथा संकलन, जीवनियाँ, संस्मरण सभी प्रकार की किताबें हैं लेखक देश-विदेश के महान लेखकों-चिंतकों के कृतियों के बीच अपने को भरा-भरा महसूस करते हैं।

लेखक मानते हैं कि उनके ऑपरेशन के सफल होने के बाद उनसे मिलने आये मराठी के वरिष्ठ कवि विंदा करंदीकर ने उस दिन सच कहा था कि ये सैकड़ों महापुरुषों के आश्रीवाद के कारण ही उन्हें पुनर्जीवन मिला है।

शब्दार्थ

• नब्ज़ - नस
• शॉक्स - चिकित्सा के लिए बिजली के दिए जानेवाले झटके।
• अवरोध - रुकावट
• सर्जन - शल्य चिकित्सक
• अर्धमृत्यु - अधमरा
• विशेषज्ञ - विशेष जानकार
• सहेजना - संभालकर रखना
• खंडन-मंडन - तर्क-वितर्क करके पुष्टि करना
• पाखण्ड - दिखावटी
• अदम्य - जिसे दबाया ना जा सके
• शैली - विधि
• प्रतिमाएँ - मूर्तियाँ
• मूल्य - आदर्श
• रूढ़ियाँ - प्रथाएँ
• कुल्हड़ - मटकेनुमा मिटटी का छोटा-सा बर्तन
• सनक - जिद
• अनिच्छा - बेमन से
• कसक - पीड़ा
• शिद्दत - अधिकता
• पुरातत्व - पुरानी बातों और इतिहास के अध्यन और अनुसंधान से संबंध रखने वाली विशेष प्रकार की विद्या
• वरिष्ठ - बड़ा
• सहमति - मंजूरी

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