Enthalpy of vaporisation of water is 40, 800 J/Mole at 1 atm. pressure. The mountain, where the pressure is 380 mm of H g, water will boil at
81.6°C
logP2P1 = ΔHvap2.303R[1T1 − 1T2]
or, log380760 = 40.8 × 1032.303 R[1373−1T2]
= 1373 − 1T2 = −0.310 × 2.303 × 8.31440.8 × 103
or, T2 = 354.6K or 81.6∘C