When a small dry piece of sodium metal is throw in water, it immediately fire. What actually happens

When a small dry piece of sodium metal is throw in water, it immediate

1.	When a small dry piece of sodium metal is throw in water, it immediately fire. What actually happens
Answer» SOLUTION :The hydrogen envolved in the reaction catches fire and HOT the sodium metal because it is a highly combustilble GAS. `2Na(s)+H_(2)O(l)to 2NaOH(aq)+H_(2)(g)`