What is the physical state of water at -
(a)25^oC
(b)0^oC
(c)100^oC

The physical states of water:

(a) at 25°C- water (liquid) 

(b) at 0°C - ice (solid)

(c)  at 100°C- water vapor (gas)

At room temperature, the molecules of water have some intermolecular force of attraction. The room temperature cannot provide sufficient heat for these molecules to overcome their force of attraction and therefore, they remain in the liquid phase.]