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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: jcais on June 16, 2006, 06:33:06 PM

Title: Cyclohexane, Freezing Point, Vaporization
Post by: jcais on June 16, 2006, 06:33:06 PM

Hello,

We had an experiment that involved finding the freezing point of cyclohexane. If some of the cyclohexane evaporates during the exp., how would this affect the freezing point determination?

I am thinking it would raise the freezing point because less of it is there so you don't need a very low freezing point. But, I don't know. Every 30 seconds the temp decreased. The Tf was 6.5C. The temp decreased. Does this mean that the vaporization of cyclo. results in a lowering of freezing point?

THank you for your help.

Title: Re: Cyclohexane, Freezing Point, Vaporization
Post by: Yggdrasil on June 16, 2006, 07:45:48 PM

Is freezing point (or temperature, in general) an extensive or intrinsic property.  In other words, do these properties depend the size of the system?  Would 1 cup of [water] freeze at a different temperature of two cups of water?

Title: Re: Cyclohexane, Freezing Point, Vaporization
Post by: jcais on June 16, 2006, 08:51:33 PM

Quote

Is freezing point (or temperature, in general) an extensive or intrinsic property.  In other words, do these properties depend the size of the system?  Would 1 cup of [water] freeze at a different temperature of two cups of water?

I think the size does not matter regarding the water, but am unsure.

Title: Re: Cyclohexane, Freezing Point, Vaporization
Post by: Mitch on June 16, 2006, 09:24:18 PM

You are right. :)

Title: Re: Cyclohexane, Freezing Point, Vaporization
Post by: jcais on June 17, 2006, 11:30:30 AM

Thank you for your help. :-)