Q 5. What is the physical state of water at-
(a) 25°C (b) 0°C (c) 100°C ?
The primary physical state of water is liquid. It converts into gaseous state at a temperature above 100 but at this temperature, it (liquid water) is in equilibrium with the gaseous state.
And Below 0 it changes into solid and also at this temperature it (liquid water) is in equilibrium with the solid state.
Therefore;
(i) At 25 water is in the liquid state
(ii) At 0 it can be liquid or solid and
(iii) At 100 it can be liquids or the gaseous state.