Why does water bubble when its hot?

Question

why does water bubble when its hot?

Answer 1

oxygen+gas

Answer 2

cause its trying to evaporate.....

Answer 3

Bubbles are nothing but gas/air trying to escape a liquid. When water gets hot enough, some of the molecules are excited beyond its boiling point, and try to escape as a gas/steam. If this steam forms below the surface of the water, you have a gas trying to escape through the water's surface, thus forming a bubble.