In which of the following beaker (I, II, III and IV) will coating on Zn be done?

1. I and III
2. II only
3. III and IV
4. IV only

The vapour density of carbon dioxide (C = 12 and O = 16) is ……………

1. 32
2. 16
3. 44
4. 22

An amphoteric hydroxide having gelatinous white precipitate is ……………

1. zinc hydroxide
2. sodium hydroxide
3. copper (II) hydroxide
4. None of the above

The element with the least electronegativity is :

1. Lithium
2. Carbon
3. Boron
4. Fluorine