September 20, 2021, 06:41:46 AM
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### Topic: Clausius Clapeyron  (Read 600 times)

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#### Jack_56

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##### Clausius Clapeyron
« on: April 28, 2021, 09:08:55 AM »
Good Day everyone.

You are given 26 g of Benzene and asked to calculate the pressure at which the sample will boil at 47 °C.
I understand we must use the integrated form of the Clausius-Clapeyron equation such that
ln(p/p*) = -ΔvapH/R (1/T - 1/T*)

At the normal boiling point of course the pressure will be 1 atm and we can substitute our values and solve for p.

However do we need to take into account the number of moles in the sample . For instance do we have to say ΔvapH = ΔvapH° x n (benzene) and use this in the equation ? If we do this the units don't seem to work out. Or does the equation function independent of the amount of substance given?
Any guidance with explanations will be really appreciated. Thanks all.

#### Borek

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##### Re: Clausius Clapeyron
« Reply #1 on: April 28, 2021, 09:29:42 AM »
Is boiling point an intensive, or extensive property?
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#### Jack_56

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##### Re: Clausius Clapeyron
« Reply #2 on: April 28, 2021, 09:38:00 AM »
Oh. I see what you're saying. Boiling point is intensive so won't depend on moles. I got confused since I was thinking about boiling point elevation (which does depend on molality). Thank you!!