## Integrals

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

Mya Majewski 1L
Posts: 89
Joined: Fri Sep 25, 2015 3:00 am

### Integrals

For calculating the work of expansion how do you properly solve an integral? I haven't had CALC in awhile and I forgot how to mathematically solve it.

Prina Patel 1H
Posts: 62
Joined: Fri Sep 25, 2015 3:00 am

### Re: Integrals

To calculate the integral you must take the antiderivative {For example, anti derivative of x is (x^2)/2} of the variables on the inside and pull out the constants if you can. Then plug in the values of the bounds you are given.
However, an easier form of the equation for expansion is w=-P delta V

Chem_Mod
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### Re: Integrals

Technically to find work of expansion you have to take the integral of -PV. If P is constant, w=-P$\Delta V$. Otherwise, with constant temperature, after integration you will get w=nRTln(V2/V1). And as the above discussion said, it is simply the anti-derivative.