Question

What is the mass of a gas that occupies 48.9 liters, has a pressure of 724 torr, a temperature of 25°,C and a molecular weight of 345 g?

Answer 1

For this question, we're going to start with the Ideal Gas Law

`PV=nRT`

We know `n` is the number of moles of the gas, which we can find by taking the mass of the gas (`m`) and dividing it by the molecular weight (`M`). Substituting this in we get:

`PV=(mRT)/M`

Solving this for `m`:

`m=(PVM)/(RT)`

Looking up the value for R with our units, gives us a value of 62.36367.

Plug in our numbers (Remember to convert Celsius to Kelvin and solve to get an answer of approximately 657g.