(a) Name a metal for each case:
- It does not react with cold as well as hot water but reacts with steam.
- It does not react with any physical state of water.
(b) When calcium metal is added to water the gas evolved does not catch fire but the same gas evolved on adding sodium metal to water catches fire. Why is it so?
(a)
- Aluminium, Iron and Zinc reacts only with steam.
- Gold and silver do not react with any physical state of water.
(b) When calcium metal is added to water, Hydrogen gas is evolved but the reaction is less violent and heat is not sufficient to catch fire. Whereas, in case when sodium is added to water, reaction is violent and exothermic reaction takes place. That’s why hydrogen gas catches fire.