# A container has a volume of 18 L and holds 9 mol of gas. If the container is expanded such that its new volume is 36 L, how many moles of gas must be injected into the container to maintain a constant temperature and pressure?

##### 1 Answer
Feb 17, 2018

Consider,

$P V = n R T$

$\implies {V}_{1} / {n}_{1} = \frac{R T}{P} = {V}_{2} / {n}_{2}$

$\therefore {V}_{1} / {n}_{1} = {V}_{2} / {n}_{2}$

Hence,

$\frac{18 \text{L")/(9"mol") = (36"L}}{n} _ 2$

$\therefore {n}_{2} \approx 18 \text{mol}$

of gas are needed to be equivalent to the conditions in the former condition.