Question

Assertion: Even after supplying heat energy to ethanol at 78°C the temperature of ethanol do not rise. Reason: At 78°C for ethanol, vapour and liquid state of the substance exist in equilibrium.

A graph between the temperature T and Pressure P of the substance is called a Phase Diagram. The following figure shows the phase diagram of water and carbon dioxide. Such a phase diagram divides the P - T plane into three regions - solid region, vapour region and liquid region