At 298 K the enthalpy of formation of liquid water is -285.9 kJ/mol and that of steam -242.8 kJ/mol. The enthalpy of vapourisation of water is
Options
(a) 43.1 kJ/mol
(b) -43.1 kJ/mol
(c) 242.8 kJ/mol
(d) -242.8 kJ/mol
Correct Answer:
43.1 kJ/mol
Explanation:
ΔH(vap) = -242.8 – (-285.9) = 43.1 kJ/mol.