How many moles are contained in each of the following at STP?

Question

(a) 23.7 L N₂

= __ mol

(b) 5.46 L Cl₂

= __ mol

(c) 0.131 L Ne

= __ mol

(d) 71.1 mL NH₃

= __ mol

Answer 1

At STP, ALL gases occupy a volume of 22.4 L per 1 mole. Knowing this, we can create the ratio of

22.4L/1 mol.

With this, we can do some simple dimensional analysis to solve!

23.7L N2 * 1 mol/22.4L = 1.05 mol N2

5.46L Cl2 * 1 mol/22.4L = 0.24 mol Cl2

Essentially, take your volume of gas and divide it by 22.4 to get your molarity.

Hope this helps!