posted by Josh .
A certain substance has a heat of vaporization of 34.65 kj/mol. At what kelvin temperature will the vapor pressure be 3.50 times higher than it was at 331 k?
Use the Clausius-Clapeyron equation.
I would make up a vapor pressure for p1 and multiply that by 3.5 for p2; alternatively you can use p1 as p1 and p2 = 3.5p1.