Q.:- What is the physical state of water at :
(a): Physical state of water at 250°C is gaseous state because the boiling point of water is 100°C. Therefore at a temperature higher than its boiling point. It exists as gas.
(b): At 100°C both liquid and gaseous states are present. These are in a state of equilibrium. So at 100°C both liquid water and vapour are present.