HYDROGEN Pg. 90 to 92

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

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

Q-2.Why granulated Zinc is used to prepare Hydrogen gas?

• Because it is cheap
• Because it contains copper impurity which has a catalyzing effect
• Because it is easily available
• NONE

Q-3: What is the method of collection of Hydrogen gas in the laboratory method of Hydrogen?

• UPWARD DISPLACEMENT OF AIR
• DOWNWARD DISPLACEMENT OF AIR
• DOWNWARD DISPLACEMENT OF WATER
• NONE

Q-4: Why Lead & dil. HCl is not used to prepare Hydrogen gas?

• INSOLUBLE LEAD CHLORIDE FORMS COATING ON THE LEAD
• SOLUBLE LEAD CHLORIDE IS FORMED
• INSOLUBLE LEAD SULPHATE WILL FORM COATING ON THE LEAD
• NONE

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

• it is a normal acid
• it is an oxyacid
• it is a strong oxidising agent so it oxidises hydrogen to water
• All the mentioned options