Question

A sample of gas has a volume of 240. L at 4.00 atm of pressure and a temperature of 1091K. What is the volume at STP?

Answer 1

`"Volume = 240.219981669L"`

Explanation:

Recall the gas law

`PV = nRT`

First we need to find moles of gas and then calculate its volume at STP

So moles of gas or n =

`n = (PV)/(RT)`

Solve the equation using formula

`n = "(4atm * 240L)"/"(0.0821L * 1091K)"`

`n = 960/89.5711"`

`n = 10.7177426648mol`

The volume of 1mol of any gas = 22.4L

Therefore volume of `10.7177426648"moles"`
`= 10.7177426648"moles" * 22.4134L = 240.219981669`

But lets still prove it

Volume of 10.7177426648moles in STP
Temperature at STP = `0^oC or 273K`
Pressure at `STP = 1atm`

`V = 10.7177426648 * 0.0821 * "273K"/"1atm"`

`V = 240.219981669/"1atm"`

`"Volume = 240.219981669L"`