The normal boiling point of water is 373 K (at 760 mm). Vapour pressure of water at 298 K is 23 mm. If enthalpy of vaporisation is 40.656 kJ/mol, the boiling point of water at 23 mm atmospheric pressure will be

Options

A. 250 K
B. 51.6 K
C. 298 K
D. 12.5 K

Answer

C

Explanation

Boiling point is the temperature at which vapour pressure becomes equal to atmospheric pressure. At 298 K vapour pressure of water, 23 mm is equal to atmospheric pressure, 23 im.