## Heat Capacity

Volume: $\Delta S = nR\ln \frac{V_{2}}{V_{1}}$
Temperature: $\Delta S = nC\ln \frac{T_{2}}{T_{1}}$

Cam Bear 2F
Posts: 60
Joined: Thu Jul 27, 2017 3:01 am

### Heat Capacity

How can you tell when something is a monatomic gas, linear molecule, or nonlinear molecule when determining the heat capacity? For example, in Example 9.6 in the book (page 329), how do you know to use 4R for the Cp,m rather than say 7/2R when cooling the acetone vapor?

Chem_Mod
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### Re: Heat Capacity

Hi, Cam,
You can just look at the molecule you study. If it's just an element by itself, like Ne, it is monoatomic. If it's a halogen, like Br2, then it is diatomic. To figure out whether the molecule is linear, you need to remember Lewis structures. HCN is linear, while acetone and water are not.