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Topic: physical chemistry,help  (Read 5023 times)

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Offline i-will-survive

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physical chemistry,help
« on: April 08, 2009, 01:45:52 AM »
I'm having trouble deriving equation for the following problems, I don't know how to start or what to do...any help would be greatly appreciated:


The heat capacity Cp,m of CHCl3(l) can be represented by Cp,m = 91.47 + 7.5*10^-2*T.

1-  Calculate (delta)H when 1 mol liquid chloroform is heated at constant pressure from 0 to 27 C. First derive the equation for (delta)H for a constant pressure temperature change.


2- Calculate (delta)S when 1 mol liquid chloroform is heated at constant pressure from 0 to 27 C. First derive the equation for (delta)S.


Thanks in advance!

Offline o0CY0o

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Re: physical chemistry,help
« Reply #1 on: April 13, 2009, 02:08:34 PM »

1-  Calculate (delta)H when 1 mol liquid chloroform is heated at constant pressure from 0 to 27 C. First derive the equation for (delta)H for a constant pressure temperature change.

delta H is given by integrating Cpm with upper limit as 27+273 and lower limit as 0+273

2- Calculate (delta)S when 1 mol liquid chloroform is heated at constant pressure from 0 to 27 C. First derive the equation for (delta)S.

delta S is given by integrating C/T with respect to T with upper limit as 27+273 and lower limit as 0+273.



If you cannot do it, i think it might be your maths more than your chem. However, i always use the calculated fx3650 to help. =P
Cheers

Offline Jazzified

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Re: physical chemistry,help
« Reply #2 on: April 21, 2009, 04:50:30 PM »
I need help also for this problem:

Using the Sackur-Tetrode equation to calculate the molar translational entropy of 20Ne: (Strans)Ne = 1039JK−1mol−1 at 1 bar and 2000K, calculate Strans for 35Cl2 under these conditions and use the energy levels of particle in a box to explain the difference between the two numbers.

EDIT (fix graphic):

I just did some "research", and found this graphic in a site, which didn't look too reliable.  Regardless, will this help me get started on this problem?

« Last Edit: April 21, 2009, 05:06:49 PM by Jazzified »

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