Page 225 - ICSE Chemistry 8

Review Your Learning

A. Answer in one word/a few words.
1. A carbon compound which is an insulator and is used to make electrical
switches and handles of various utensils _______________
2. The purest form of carbon _______________
3. A spherical, crystalline allotropic form of carbon consis ng of 60 atoms _______________

4. The process in which break down of an organic substance takes place
when it is heated in the presence of air _______________
5. A type of charcoal that is used to remove fl uoride from water _______________
6. A variety of coal which contains over 90% of carbon _______________

B. State whether the given statements are true (T) or false (F).
1. Polythene is used to make items such as carry bags, pipes and household ar cles.

2. All forms of carbon diff er in their physical proper es.
3. Graphite is used in making crucibles for mel ng metals due to its low mel ng point.
4. Wood charcoal is a bad conductor of electricity.
5. The fi rst step of coal forma on begins with lignite.

6. Carbon dioxide is a colourless gas that cons tutes about 0.04% of air by volume.
C. Explain the following terms.

1. Organic compounds 2. Allotropy 3. Wood gas
4. Carbonisa on 5. Dry ice 6. Global warming

D. Answer the following ques ons.
1. Write some useful carbon products and state their uses.
2. Discuss about the allotropes of carbon.
3. Write the proper es and uses of graphite.

4. Write a note on amorphous forms of carbon.
5. How is coal formed? What are the diff erent types of coal?
6. Write the physical and chemical proper es of carbon dioxide.

7. With the help of an ac vity, show that carbon dioxide is heavier than air and does not support
combus on.

8. What are the uses of carbon dioxide?
9. How can the concentra on of carbon dioxide in the atmosphere be balanced?
10. How is carbon monoxide formed? How is carbon monoxide added to the atmosphere?

PROJECT

Create a PowerPoint presenta on on the topic ‘Greenhouse Eff ect’. 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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