HYDROGEN Pg. 97 & 98 (B1)

Q1. Name an element which reacts violently with water at room temperature.

• a. Sodium.
• b. Calcium.
• c. Iron.
• d. Gold.

Q-2.Why lead & dil. HCl cannot be used to prepare Hydrogen gas?

• Lead does not react with dil. HCl
• Insoluble PbCl2 coating is formed on the lead which stops the reaction
• Both Lead does not react with dil. HCl & Insoluble PbCl2 coating is formed on the lead which stops the reaction
• NONE

Q3. A metal below iron but above copper in the activity series of metals which has no reaction with water.

• a. Zn
• b. Fe
• c. Pb.
• d. Hg.

Q4. The salt formed when aluminium reacts with potassium hydroxide , during the preparation of hydogen from alkalis.

• a. Potassium aluminate .
• b. Potassium zincate.
• c. Potassium plumbite.
• d. None of the above.

Q-5. Why dil. nitric acid is not used to prepare hydrogen gas?

• it is a normal acid
• it is oxyacid
• it is a strong oxidising agent so it oxidises hydrogen to water
• NONE