Page 119 - ICSE Chemistry 6

Review Your Learning

A. Answer in one word.
1. The layer of air that surrounds the earth ______________

2. The process by which plants make their own food ______________
3. Gases and par cles in the atmosphere that harm organisms and aff ect climate ______________
4. The trapping of heat energy of the sun by greenhouse gases present in the
earth’s atmosphere ______________

5. The increase in the average temperature of the earth’s atmosphere ______________

B. State whether the given statements are true (T) or false (F).
1. Nitrogen does not support combus on.
2. Burning of coal gives off carbon dioxide and water vapour along with smoke and ash.

3. CNG on burning gives out a large amount of carbon dioxide, thereby pollu ng air.
4. Chlorofl uorocarbons destroy the ozone layer.

5. Smog is the combina on of rain drops with sulphur dioxide.

C. Match the columns.
Column A Column B
1. Oxygen (a) Evapora on and boiling of water

2. Solid carbon dioxide (b) Fossil fuels
3. Water vapour (c) Reduced fer lity of soil
4. Coal and petroleum (d) Supporter of combus on

5. Acid rain (e) Dry ice

D. Explain the following terms.
1. Nitrogen fi xa on 2. Respira on 3. Fuels 4. Global warming 5. Acid rain

E. Answer the following questions.

1. Give evidences to confi rm that air is a mixture.
2. Write the uses of oxygen and carbon dioxide.
3. Write a note on the importance of air.

4. Write the similari es and diff erences between respira on and combus on.
5. Write the eff ects of air pollu on. What steps should be taken to reduce air pollu on?

PROJECT

Create a presenta on on the topic ‘Air and Its Composi on’. Find the related informa on and images
using the Internet. Add audio and visual eff ects to your presenta on. Format it as per your choice.

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