Question

A container has a volume of `3 L` and holds `1 mol` of gas. If the container is expanded such that its new volume is `8 L`, how many moles of gas must be injected into the container to maintain a constant temperature and pressure?

Answer 1

`5/3` moles

Explanation:

For solving this problem we have to assume the ideal behaviour of the gas.
Hence the equation `PV=nRT` can be applied.
Now the volume is increased by a factor of `8/3` `:.` number of moles should also increase by a factor of `8/3`
`:.` new number of moles `=1xx8/3=8/3`
`:.` extra moles which we have to inject are `8/3-1=5/3` moles