PV = nRT


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Lauryn Jordan 1F
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PV = nRT

Postby Lauryn Jordan 1F » Tue Feb 13, 2018 6:50 pm

when do you use PV = nRT?

Kaylin Krahn 1I
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Re: PV = nRT

Postby Kaylin Krahn 1I » Tue Feb 13, 2018 7:44 pm

When dealing with an ideal gas and if you are looking for one of the variables and given the others. You're not really directed to use it, but you use it to find a missing variable that you might need. For example, if you need to use volume but you're given moles, temperature, and pressure. Also, work is equal to both -p delta v and -nRT so it depends on what you're given.

Beza Ayalew 1I
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Re: PV = nRT

Postby Beza Ayalew 1I » Wed Feb 14, 2018 4:11 pm

if you're using delta v, you're probably going to be using delta nRT, so that something to consider as well

Beza Ayalew 1I
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Re: PV = nRT

Postby Beza Ayalew 1I » Wed Feb 14, 2018 4:12 pm

Also can someone explain why you have delta nRT, but not nRdeltaT? I feel like I've seen the second one being used but usually the change goes towards the number of moles.

Angela G 2K
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Re: PV = nRT

Postby Angela G 2K » Wed Feb 14, 2018 4:52 pm

Delta nRT is used to calculate the change in internal energy under constant pressure. Delta U = q + w, but under constant pressure it becomes


A change in volume is often due to a net change in gas molecules, so . Substitute in and you get .

Jennie Fox 1D
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Re: PV = nRT

Postby Jennie Fox 1D » Wed Feb 14, 2018 8:37 pm

For ideal gases when you need to solve for a constant.

mayapartha_1D
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Re: PV = nRT

Postby mayapartha_1D » Mon Feb 19, 2018 3:13 pm

You use this equation for ideal gases! If in a problem, you are given a pressure and the other variables, and it is stated that the given substance is an ideal gas, you will use this equation.

Hope this helped,
Maya


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