Exercise 8.31

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Aijun Zhang 1D
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Joined: Tue Oct 10, 2017 7:13 am

Exercise 8.31

Postby Aijun Zhang 1D » Sun Jan 14, 2018 2:42 pm

Can someone explain how to do the constant pressure and volume question?
8.31 Calculate the heat released by 5.025 g of Kr(g) at 0.400 atm as it cools from 97.6 C to 25.0 C at (a) constant pressure and (b) constant volume. Assume that krypton behaves as an ideal gas.
I'm really confused with these constant values now since the topic I familiar with is just specific heat capacity.

Thanks!

Chem_Mod
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Re: Exercise 8.31

Postby Chem_Mod » Sun Jan 14, 2018 3:33 pm

The equation used for calculating heat released is q=mCΔT. Since we are told that Kr behaves as an ideal gas, we can use the specific heat capacity for ideal gases at constant pressure (Cp=5/2R) and at constant volume (Cv=3/2R).

torialmquist1F
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Re: Exercise 8.31

Postby torialmquist1F » Sun Jan 14, 2018 8:52 pm

Chem_Mod wrote:The equation used for calculating heat released is q=mCΔT. Since we are told that Kr behaves as an ideal gas, we can use the specific heat capacity for ideal gases at constant pressure (Cp=5/2R) and at constant volume (Cv=3/2R).


Where does the 5/2R come from?

Lourick Bustamante 1B
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Joined: Wed Nov 16, 2016 3:02 am

Re: Exercise 8.31

Postby Lourick Bustamante 1B » Mon Jan 15, 2018 5:18 pm

It's a given! It's explained in Chapter 8.10 of the textbook! (:


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