Ideal Gases Formula

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

004643111
Posts: 14
Joined: Fri Sep 25, 2015 3:00 am

Ideal Gases Formula

Why is it that for the equation deltaS=nRln(P1/P2), the change in pressure goes from initial to final instead of final over initial, like for ideal gases' change in temperature?

Tram Ha 3I
Posts: 11
Joined: Fri Sep 25, 2015 3:00 am

Re: Ideal Gases Formula

It's because we apply the initial and final pressures according to Boyle's law. Boyle's law says that pressure is inversely proportional to volume: as the pressure of the system increases, its volume decreases. So we have V1P1 = V2P2. From this equation we get V2/V1 = P1/P2