Question

What volume is occupied by a `7*g` mass of dinitrogen gas at a temperature of `300*K`, and a pressure of `750*mm*Hg`?

Answer 1

`V~=6*L`

Explanation:

Given `V=(nRT)/P`, we know that nitrogen (LIKE most of the elemental gases) is a DIATOM, i.e. `N_2`. We also know that `760*mm*Hg-=1*atm.` This is a key point, as we can use the height of a mercury column as an accurate representation of pressure.

So `V=((7.0*g)/(28.0*g*mol^-1)xx0.0821*(L*atm)/(K*mol)xx300*K)/((750*mm*Hg)/(760*mm*Hg*atm^-1))`

All units EXCEPT `"litres"` cancel, so...........

`~=6*L.......`