#Na_3N# decomposes to form sodium and nitrogen gas at STP. If 13.7 L of nitrogen is produced, how many moles of #Na_3N# was used (22.4 L = 1 mole of any gas) ?

1 Answer
Jul 29, 2017

Answer:

#1.22# mol #Na_3N#

Explanation:

Given: #Na_3N# decomposes to form sodium (Na) and Nitrogen (#N_2)# at STP (standard temperature and pressure). At STP #22.4 L = 1# mole of gas

First you need to write a skeleton equation and then balance it. You need to realize that nitrogen is a diatomic element #N_2#.

skeleton equation: #" "Na_3N -> Na + N_2#

balanced: #" "2Na_3N -> 6Na + N_2#

The balanced equation gives us the mole ratio of sodium nitrate to nitrogen produced: #2/1#.

#13.7 cancel(L N_2) xx (1 cancel(mol N_2))/(22.4 cancel(L N_2)) xx (2 mol Na_3N)/(1 cancel(mol N_2)) = 1.22" mol "Na_3N#