# Question #e9ae8

##### 1 Answer

#### Answer:

#### Explanation:

Let

Given:

The Ideal Gas law is:

We are not given the volume but we do not need it; the reason will soon become obvious. Solve for the Volume per Moles:

I am taking an extra step to show you that the Numbers for temperature and pressure cancel and and their units are canceled by the gas constant:

No matter what Volume or number of moles we pick, at this temperature and pressure, the following ratio is true:

We are given the mass density:

To find the Molar Mass, we use the Factor-Label Method (a.k.a. Dimensional Analysis):