Page 129 - ICSE Chemistry 6

18. How are aqua c animals and plants able to survive in colder regions of the world?
19. What is latent heat of vaporiza on?
20. What is chlorina on?
21. Discuss the composi on of air.
22. How is the amount of nitrogen balanced in the air?
23. What is the importance of carbon dioxide?
24. What is the role of oxygen in respira on?
25. What is combus on?

D. Answer in detail.
1. How does chemistry help us?
2. Discuss the contribu on of the alchemists.
3. Write a note on some important scien sts and their contribu ons.
4. Write a note on ‘food and chemistry’.
5. Write a note on ‘clothing and chemistry’.
6. Diff eren ate between metals and non-metals.
7. Write the characteris cs of compounds.

8. Write the characteris cs of atoms and molecules.
9. Diff eren ate between compounds and mixtures.
10. Why is water a compound and air a mixture?
11. With the help of an ac vity, show that ma er occupies space.
12. With the help of an ac vity, show that solids have defi nite volume.
13. Write the proper es of liquids.
14. Discuss the eff ect of heat on ma er.

15. With the help of an ac vity, show that a liquid expands on hea ng and contracts on cooling.
16. With the help of an ac vity, show that plants require fresh water to grow.
17. ‘Water is a universal solvent.’ Explain.
18. What is the need to conserve water? Write the steps to conserve water.
19. What is water pollu on? What are the causes of water pollu on?
20. (a) Write the steps that can be taken to prevent water pollu on.
(b) How are fl oods and droughts caused? What are their eff ects?
21. Discuss the evidences to confi rm that air is a mixture.
22. With the help of an ac vity, show that oxygen supports combus on.

23. Give the similari es and diff erences between respira on and combus on.
24. With the help of an ac vity, show that green plants produce oxygen during photosynthesis.
25. Write the causes and eff ects of air pollu on? What measures can be taken to reduce air pollu on?

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