Selina solutions for Concise Chemistry [English] Class 6 ICSE chapter 6 - Air and Atmosphere [Latest edition]

What is atmosphere?

Why can’t we see air?

What is wind?

What would have happened if there would have been no atmosphere around the earth?

When water is heated, we see bubbles rising up. Why?

Why is air called a mixture? Give five facts in support of your answer.

What are the main components of air?

Write down the composition of three main gases present in air by volume.

What do you observe when Ice cold water is filled in a glass tumbler.

What do you observe when a burning candle is covered with an inverted jar.

What do you observe when Carbon dioxide gas is passed through lime water.

What do you observe when a beam of light is allowed to enter in a closed dark room through a small hole.

Write the chemical name of Lime water

Write the chemical name of The white insoluble solid formed on the reaction of carbon dioxide with lime water.

Name two important processes supported by oxygen present in air.

Give two uses of the following component present in air:

oxygen

Give two uses of the following component present in air:

nitrogen

Give two uses of the following component present in air:

carbon dioxide

Give two uses of the following component present in air:

water vapour

Define the following:

Respiration

Define the following:

Photosynthesis

Define the following:

Combustion.

What are fuels?

Give two examples of modern fuels.

Give reason:

Aquatic animals and plants are able to survive in the matter.

Give reason:

A burning candle stops burning if covered with a glass tumbler

Give reason:

Mountaineers and divers carry oxygen cylinders with them.

Give reason:

When water is heated, we see bubbles rising up.

Name the processes which maintain the balance between oxygen and carbon dioxide in the air. How is it done?

State two similarities and two differences between respiration and burning.

Define rusting?

What are the two necessary conditions for rusting of iron?

Give the chemical name of rust.

How is air useful to water boats?

How is air useful to agriculture?

How is air useful to windmills?

How is air useful to scooters and cars.?

State the full form of LPG and CNG? How are the two different in their composition?

Why is nitrogen important to all living beings?

What is nitrogen fixation?

What is air pollution?

Mention five causes of air pollution.

Name two air pollutants which affect our health.

Name two air pollutants which cause acid rain.

Name two air pollutants which cause global warming.

What is meant by ozone depletion?

State four steps to be taken to control air pollution.

Name three greenhouse gases.

Fill in the blank

The layer of air around the earth is called the ________.

Fill in the blank

Although we cannot see air, we can ___it.

Fill in the blank

Air is a ______ of gases

Fill in the blanks

Plants and animals maintain the balance of carbon ___________and _________ in the air.

Fill in the blank

Polluted air is harmful to ____.

Fill in the blank

The supporter of combustion in air is _____.

Fill in the blank

Green plants need ________________to prepare food.

Fill in the blanks

Oxygen is used in ___________the food to get _______.

Fill in the blank

Aquatic plants and animals use _________ in water.

Fill in the blank

The reddish-brown powder on the surface of iron nails exposed to air and moisture is called _____.

Write ‘true’ or ‘false for the following;

Air is a compound.

Write ‘true’ or ‘false for the following;

Carbon dioxide is given out during photosynthesis

Write ‘true’ or ‘false for the following;

The composition of air was discovered by Lavoisier.

Write ‘true’ or ‘false for the following;

The major component of air is oxygen.

Tick (√) the correct alternative from the choice given for the following statement.

Air consists of

Tick (√) the correct alternative from the choice given for the following statement.

Air pollution is due to the

Tick (√) the correct alternative from the choice given for the following statement.

The gases which cause acid rain are

Tick (√) the correct alternative from the choice given for the following statement.

Rust is

Tick (√) the correct alternative from the choice given for the following statement.

Photosynthesis is a process in which plants

Tick (√) the correct alternative from the choice given for the following statement.

Fuels which do not leave any residue on burning are

Tick (√) the correct alternative from the choice given for the following statement.

Respiration

Tick (√) the correct alternative from the choice given for the following statement.

Which of the following is not a greenhouse gas?

Tick (√) the correct alternative from the choice given for the following statement.

The substance which accelerates the speed of a reaction without itself undergoing any change is called

State what do you understand by the term ‘air’. Explain its importance to mankind.

Give a brief account of the discovery of air and the scientists involved.

What is meant by the term ‘atmosphere’? State the role played by the atmosphere for the survival of mankind.

Explain in brief the different layers of the atmosphere and the basic functions of the main layers.

Describe a simple experiment with the help of a diagram to show that Air occupies space

Describe a simple experiment with the help of a diagram to show that Air has mass

Describe a simple experiment with the help of a diagram to show that Air exerts pressure

Describe a simple experiment with the help of a diagram to show that Air is highly compressible

Name the components of air with their approximate percentage by volume in air. Does the percentage by volume of each component remain the same, in the atmosphere of different parts of the world? Explain with reasons.

With the help of a labeled diagram, describe a simple experiment to show the presence of oxygen and nitrogen in air using a piece of white phosphorus.

You are given a test tube with two outlets and a bottle of lime water. Using same, how would you demonstrate experimentally the presence of carbon dioxide in air.

Give a reason why water droplets appear on the outer surface of a tumbler containing ice.

Explain the importance of nitrogen of the air for plant growth.

Give a reason why nitrogen is filled in food packets and not oxygen.

State what would happen, if the air above the earth contained mainly oxygen and no nitrogen

State the utility of oxygen for respiration in living organisms

State the utility of oxygen for respiration in plants

Explain the importance of carbon dioxide for (a) photosynthesis (b) warming the earth’s environment. State what would happen if excess carbon dioxide as a pollutant is released into the atmosphere.

State in brief how water vapour in the atmosphere determines the climatic conditions

Give a reason why two different rare (inert) gases find application in advertisement signs and fluorescent bulbs.

A mixture has a variable composition. Give three other reasons why air is considered a mixture and not a compound.

State a reason why there is a balance in the amount of carbon dioxide in the air, even though carbon dioxide is released into the atmopshere by various processes.

Name three different appliances where air is utilized.

Match the statements in List 1 with the correct answers in List 2

The diagrams below represents an experiment to show the presence of a component of air.

1. State why air is sucked from – outlet ‘B’ and not from outlet “A”
2. State why the air is sucked ‘slowly’ from the outlet “B”
3. State the observation seen after completion of the experiment.
4. State the reason for the above observation seen.
5. Name another component which if present in air as a pollutant would have given a similar observation

Complete the statement given below by filling in the blank with the correct word from the words given below

The ______ is a layer which extends up to about 10-50 km. above the earth.

Complete the statement given below by filling in the blank with the correct word from the words given

___________is an example of a pollutant present in the air.

Complete the statement given below by filling in the blank with the correct word from the words given:

The component of air used in photosynthesis is ______ and the products of photosynthesis is oxygen.

Complete the statement given below by filling in the blank with the correct word from the words given:

The product formed which is common to both combustion and respiration is ______.

Complete the statement given below by filling in the blank with the correct word from the words given:

The component of air which is variable in air above sea level and in air in general ______.

Name the following:

The product formed when phosphorus burns in oxygen.

Name the following:

The layer of atmosphere which contains the ozone layer.

Name the following:

The active component of air which supports combustion and is used up in burning

Name the following:

The main, rare (inert) gas present in air.

Name the following:

The component of air which is present more in industrial areas.

Name the following:

The type of bacteria which directly absorb nitrogen from the air and converted soluble nitrates in the soil.

Name the following:

The product of respiration released in exhaled air, other than carbon dioxide.

Name the following:

An inert gas which has a low boiling point and is used for producing very low temperatures

Name the following:

A process which removes carbon dioxide from the air.

Name the following:

The component of air which does not support combustion.

State whether the following statement is ‘true’ or ‘false’. If false write the correct statement.

The mesosphere in the atmosphere, contains most of the air, fit for respiration

State whether the following statement is ‘true’ or ‘false’. If false write the correct statement.

The percentage of carbon dioxide in the air is between 0.2 to 0.4%.

State whether the following statement is ‘true’ or ‘false’. If false write the correct statement.

Carbon dioxide, water vapour and energy in the form of heat are evolved during respiration.

State whether the following statement is ‘true’ or ‘false’. If false write the correct statement.

Photosynthesis is a process by which green plants prepare their own food in the presence of sunlight and chlorophyll.

State whether the following statement is ‘true’ or ‘false’. If false write the correct statement.

Air is a mixture and not a compound since the components of air cannot be separated by physical methods.

Give word equation for the following conversion:

Nitrogen of the air to nitric oxide

Give word equation for the following conversion:

Nitric oxide to nitrogen dioxide

Give word equation for the following conversion:

Nitrogen dioxide to nitric acid

Give word equation for the following conversion:

Nitric acid to soluble nitrates in the soil

Give word equation for the following conversion:

Carbon dioxide in the air to carbohydrates in plants.