The volume occupied by 3 moles of N2 at 0 degree C and 101.325 kPa is:
a. 22.4 dm3
b. 67.2 dm3
c. 7.47 dm3
d. 134.4 dm3

Hi teatea!!

101.325 kPa is equal to 1 atm. 

We will use the Ideal Gas Law: 
 
PV = nRT 

1 atm x V = 3 mol x (0.082058 (L.atm)/(mol * K)) x 273K = 67.205502
L.atm

Then 

V = 67.2 L = 67.2 dm3.

The correct answer is b.

Another way:
You know that the volume of one mol of ANY ideal gas at standard
temperature and pressure (273K and 1 atm) is 22.4 L, then 3 moles will
ocupe:
V = 3 x 22.4 L = 67.2 L = 67.2 dm3

Hope this helps.

Regards.
livioflores-ga