Problem 8.31

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Problem 8.31

Postby hannah_flagg_3F » Mon Jan 30, 2017 11:18 am

The problem asks you to calculate the heat released by 5.025 g of Kr(g) at 0.400 atm as it cools from 97.6 C to 25 C at (a) a constant pressure and (b) a constant volume.

Now, I know you use the formula Cp=5/2R to solve for the heat capacity for constant pressure and Cp=3/2R to solve for the heat capacity for constant volume, and you use the R value, 8.314 J/K*mol. In the solution manual, it solves the problem by leaving the temperature change in degrees celsius, but the gas constant you use has the temperature in Kelvin. So why the discrepency?

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Re: Problem 8.31

Postby mikezargari » Mon Jan 30, 2017 2:30 pm

The units for delta T are arbitrary because the difference between your final T and initial T are going to be the same whether you are calculating it in celsius or kelvin.

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