I am doing a lab writeup and am completely lost.(adsbygoogle = window.adsbygoogle || []).push({});

Summary of lab itself:

- Calculated the vapour pressure of chloroform (TCM) across a range of temperatures (using flask apparatus).
- Objective is to determine the heat of vaporization of TCM using the variation of vapour pressure with temperature.

Other info we are provided:

- Provided the Clausius-Clapeyron relation (lnP = -ΔH
_{v}/RT + C)- "is independent of temperature"
- "C is a constant related to the entropy of vaporization"

I'm supposed to:

- plot P
_{vapor}vs. T, and determine the boiling temp.- plot lnP
_{vapor}vs. 1/T, and determine ΔH_{vapor}

My questions:

- How do you calculate boiling point from this data? I am assuming it involves extrapolating and determining at what temperature P
_{vapor}= P_{barometric}?- How do you calculate ΔH
_{vapor}from this data without knowing C? That is, how are lnP_{vapor}and 1/T related to C? (we are not given C and are supposed to determine it from the data)

Help would be appreciated.

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# Calculating the heat of vaporization of chloroform [thermochemistry]

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