How many moles of #N_2# are formed by the decomposition of 2.5 moles of #NaN_3#?

2 Answers
Feb 16, 2016

#3.75molN_2#

Explanation:

The decomposition reaction of sodium azide #NaN_3# is:

#2NaN_3(s)->2Na(s)+3N_2(g)#

Using dimensional analysis, we can find the number of mole of #N_2# gas formed:

#?molN_2(g)=2.5cancel(mol NaN_3)xx(3molN_2)/(2cancel(molNaN_3))=3.75molN_2#

Feb 16, 2016

#5.8 mols#

Explanation:

first multiply the mols with the mr #65*2.5=162.5#
then use this to get the mols of #N_2#
#mols=162.5/28#
#mols=5.8#