Page 163 - ICSE Chemistry 8

4. The process of removing oxygen on adding hydrogen to an element or a
compound is called oxida on. _________________
5. A substance that brings about reduc on is called an oxidising agent. _________________
6. In a displacement reac on, both oxida on and reduc on occur
simultaneously. _________________

C. Discuss the reac on of hydrogen with each of the following.

1. Litmus 2. Oxygen 3. Chlorine 4. Nitrogen
5. Carbon 6. Carbon dioxide 7. Sulphur 8. Metals

D. Match the columns.

Column A Column B
1. Henry Cavendish (a) Produc on of ammonia gas
2. Electrolysis (b) Forma on of metal hydrides

3. Antoine Lavoisier (c) Cu ng and welding of metals

4. Haber’s process (d) Called hydrogen an infl ammable air
5. Hydrogen reac ng with highly reac ve metals (e) Passing of electricity through acidulated water
6. Oxy-hydrogen fl ame (f) Named hydrogen

E. Complete the following equa ons and balance them.
1. Na + H O _________ + H 
2
2
2. Zn + HCl ZnCl + _________
2
3. Al + H O _________ + H 
2
2
4. Fe O + H _________ + _________
3
2
2
5. Mg + H SO _________ + H 
2
2
4
6. Pb + _________ Na PbO + H 
2
2
2
F. Choose the correct op on.
1. _____________ is the lightest of all the gases.
(a) Helium (b) Hydrogen (c) Oxygen (d) Argon
2. Which of the following subatomic par cles is/are not present in an atom of hydrogen?
(a) Electron (b) Proton (c) Neutron (d) Both (b) and (c)

3. Who gave the name ‘hydrogen’?
(a) Henry Cavendish (b) Antoine Lavoisier
(c) Paracelsus (d) None of these

4. Hydrogen can be prepared by the displacement of hydrogen from
(a) water by more reac ve metals. (b) dilute acids by more reac ve metals.
(c) alkalis by more reac ve metals. (d) all of these.

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