## Gas constant

$w=-P\Delta V$
and
$w=-\int_{V_{1}}^{V_{2}}PdV=-nRTln\frac{V_{2}}{V_{1}}$

Minh Ngo 4G
Posts: 137
Joined: Thu Jul 25, 2019 12:17 am

### Gas constant

A piston confines 0.200mol Ne(g) in 1.20L at 25C. part (a)The gas is allowed to expand through an additional 1.20L against a constant pressure of 1.00 atm.
b) The gas is allowed to expand reversibly and isothermally to the same final volume.
So I want to calculate the work done for part b but I don't know what gas constant to use. Do I use 3.314 or 8.206? Thanks

Asha Agarwal 1E
Posts: 51
Joined: Fri Aug 30, 2019 12:16 am

### Re: Gas constant

When choosing a gas constant, you need to look at the units in the problem. Since you are given atm, use the gas constant 0.0821.

MaggieHan1L
Posts: 100
Joined: Thu Jul 11, 2019 12:17 am

### Re: Gas constant

Where are you getting 3.314?

205405339
Posts: 77
Joined: Thu Jul 11, 2019 12:16 am

### Re: Gas constant

use the gas constant that matches the units given in the question

Callum Guo 1H
Posts: 134
Joined: Fri Aug 02, 2019 12:15 am
Been upvoted: 1 time

### Re: Gas constant

There is a chart of gas constants. Match up R with the correct units.

AronCainBayot2K
Posts: 101
Joined: Fri Aug 30, 2019 12:17 am

### Re: Gas constant

Gas constant values are dependent on the unit of pressure. Since atm is given, you would use the constant with atm as the units present.