Question

Help Please! =( Thanks in advance =D A certain substance has a heat of vaporization of 59.42 kJ/mol. At what Kelvin temperature will the vapor pressure be 7.50 times higher than it was at 347 K?

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As a hint, I am told to use the Clausius-Clapeyron equation- but I'm not sure how to go about finding the answer....

Answer 1

you might be having the expression for Clausius - Clapeyron equation,

given,
inital pressure / final pressure
enthalpy of vapourisation
initial temperature

you just need to plug in the values in the equation.
you will get the final temperature,,, that will be your answer.

Answer 2

you wanna make the ratio of pressure 7.5

so you have \[\ln \frac{ P _{1} }{ P _{2} }=\frac{ H _{vap} }{ R }(\frac{ 1 }{ T _{2} }-\frac{ 1 }{ T _{1} })\]

then:

P1=7.5 and P2=1

\[\ln \frac{ 7.5 }{1 }=\frac{ H _{vap} }{ R }(\frac{ 1 }{ 347 K}-\frac{ 1 }{ T _{1} })\]