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### Determining Expansion Work

Posted: Wed Feb 12, 2020 9:16 am
How can you tell whether a system does expansion work by just looking at the gas moles on both sides of the equation?

### Re: Determining Expansion Work

Posted: Wed Feb 12, 2020 11:15 am
If there are more moles of gas on the product side than the reactant side, then the reaction did expansion work (expanded to more moles of gas). On the other hand, if there are fewer moles of gas on the product side, this means the system was compressed.

When calculating the number of moles of gas on either side, don't forget to take into account the COEFFICIENTS!!

Hope this helped!

### Re: Determining Expansion Work

Posted: Fri Feb 14, 2020 4:23 pm
By comparing the moles of gas on the reactant and products sides of the balanced equation, you can tell if the system has done expansion work. If moles of R > moles of P, the system has compressed. If moles R < moles of P, the system has expanded. This is all assuming that this is an open system and volume can change.

### Re: Determining Expansion Work

Posted: Fri Feb 14, 2020 5:17 pm
if there was a change in the number of moles, the system had done expansion work (if the volume can change)

### Re: Determining Expansion Work

Posted: Fri Feb 14, 2020 9:39 pm
You can tell when a system does expansion work if the number of moles of gas on the product side is greater than the number of moles on the reactant side.