Question

A container has a volume of `2 L` and holds `1 mol` of gas. If the container is expanded such that its new volume is `4 L`, how many moles of gas must be injected into the container to maintain a constant temperature and pressure?

Answer 1

We must inject `1mol`

Explanation:

The Ideal Gas Law is

`PV=nRT`

`V/n=RT/P`

`V/n=k`

Where `k=`constant

`V_1/n_1=V_2/n_2`

`V_1=2L`

`n_1=1mol`

`V_2=4L`

`n_2=V_2/V_1*n_1`

`=4/2*1=2mol`

We must inject `2-1=1mol`