Substituting -nrT for -PΔV


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Layal Suboh 1I
Posts: 61
Joined: Fri Sep 28, 2018 12:23 am

Substituting -nrT for -PΔV

Postby Layal Suboh 1I » Tue Feb 12, 2019 10:12 pm

Hello,

When substituting -nrT for -PΔV, how do you know what changing (moles or temperature)?

Jim Brown 14B Lec1
Posts: 62
Joined: Fri Sep 28, 2018 12:28 am

Re: Substituting -nrT for -PΔV

Postby Jim Brown 14B Lec1 » Tue Feb 12, 2019 11:02 pm

It will say in the question. Isothermal, same T, moles have to change. Increased Temperature, T changes.

Tatum Keichline 2B
Posts: 64
Joined: Fri Sep 28, 2018 12:26 am

Re: Substituting -nrT for -PΔV

Postby Tatum Keichline 2B » Tue Feb 12, 2019 11:07 pm

n and r are constant if T changes, but r and T are constant if the system is isothermal (same temperature)

Dimitri Speron 1C
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Re: Substituting -nrT for -PΔV

Postby Dimitri Speron 1C » Thu Feb 14, 2019 9:54 am

You have to balance the chemical equation to see if the number of moles of gas will change. For the temperature the problem will tell you.

Brandon Mo 4K
Posts: 70
Joined: Fri Sep 28, 2018 12:15 am

Re: Substituting -nrT for -PΔV

Postby Brandon Mo 4K » Thu Feb 14, 2019 11:21 pm

The temperature would be given in the problem. To find delta n, you balance the chemical equation and take the difference of moles of gas between the products and reactants.


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