How do I calculate the boiling point of water at a specific atmospheric pressure?

Question

In Breckenridge, Colorado, the typical atmospheric pressure is 520 tore. What is  the boiling point of water in Breckenridge? Delta H (vaporization)= 40.7 kJ/mol.

Answer 1

In this type of question, you'll want to familiarize yourself with the Clausius-Clayperyon equation.

ln P₁/P₂ = ∆H_vap/R (1/T₂ - 1/T₁) where R = 8.314 J/mol-K and T is in degrees K

P1 = 760 torr

P2 = 520 torr

T1 = 373 K

T2 = ?

∆H_vap = 40.7 kJ/mole

R = 0.008314 kJ/mole-K (NOTE: change R to units of kJ)

Plug in and solve for T2