Answer to Question #174725 in Organic Chemistry for Tuhin Subhra das

Question

Give the significance of critical point in the phase diagram of water.

Answer 1

Water expands and becomes less dense until, at the critical point, the densities of liquid and vapour become equal, eliminating the boundary between the two phases. If the average density at the start is too low, all the liquid will evaporate before the critical temperature is reached.

In water, the critical point occurs at 647.096 K (373.946 °C; 705.103 °F) and 22.064 megapascals (3,200.1 psi; 217.75 atm).