PV = nRT
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Re: PV = nRT
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.
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Re: PV = nRT
if you're using delta v, you're probably going to be using delta nRT, so that something to consider as well
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Re: PV = nRT
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.
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Re: PV = nRT
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 .
A change in volume is often due to a net change in gas molecules, so . Substitute in and you get .
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Re: PV = nRT
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
Hope this helped,
Maya
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