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Jerzey2Atl
Jul20-04, 05:56 PM
Hi, this is my first time using this forum. I have a question dealing with entropy and thermodynamics.

Here goes:

According to Debye’s law, the molar heat capacity at constant volume of a
diamond varies with temperature according to the relation

Cv = (12*pi^4*R / 5) x (T / TD)^3

where TD = 2230 K. For a diamond of mass 1. 20 g, what is its entropy change when it is heatedat constant volume from 10. 0 K to 350 K? The molar mass of carbon is 12. 0 g/mol.

I know Ih ave to first find the molar mass, but I am not sure of which form of the entropy equation to use. Any help is appreciated.

PureEnergy
Jul20-04, 11:59 PM
To solve the problem you can use this equation to find the molar entropy

\Delta S = \int_{T_1}^{T_2} C_v \frac{dT}{T}

Multiply this result by the numer of moles (1.2/12) to get entropy in terms of energy/time.

Jerzey2Atl
Jul21-04, 08:29 PM
Thanks a lot....imma try this.