Bharath heated a closed vessel full of water. After some time he observed that the water started boiling and after some more time there is no water in the vessel. This is an example of:
Reversible change
Physical change
Physical change refers to changes that can be undone whereas chemical change refers to the changes that can't be undone.
When water is boiled into steam it is a reversible change as the steam can be condensed and converted back into the water.