### density

Posted:

**Wed Jan 29, 2020 10:29 am**how can you use density in PV=nRT?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=123&t=57626

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Posted: **Wed Jan 29, 2020 10:29 am**

how can you use density in PV=nRT?

Posted: **Wed Jan 29, 2020 11:19 am**

Since density is mass over volume, you can substitute the mass in n and the volume in v in the equation pv = nrt. Once this is done, the equation can be rewritten as molar mass = dRT/P.

Posted: **Mon Feb 10, 2020 8:48 am**

The density can be used toward PV=nRT when there are problems that doesn't give you the moles of the molecule. For example, a problem might give you the amount in mL, and so we'd convert it to moles via density (at least that's what I've been told through the sessions). Hope that helps!

Posted: **Mon Feb 10, 2020 9:30 am**

Density is mass/volume (g/cm^3) and can be substituted into the ideal gas equation using algebra.

Posted: **Mon Feb 10, 2020 10:08 am**

Density is given in g/mL. Sometimes, the problem gives the amount of a substance in mL, and you can convert this value to grams and then moles to find the 'n' in PV=nRT.

Posted: **Sun Feb 16, 2020 3:08 pm**

You can use density to find "n" or even replace "n" in PV=nRT since density is mass/volume