The Haber process developed to produce fertilizer from nitrogen and hydrogen, is governed by the following unbalanced reaction:

a N2 + b H2 -> c NH3
.
If 10.5 kg of NH3 product is required, how many kg of hydrogen are required if nitrogen is in excess?

1 answer

so balance it. then you have the ratio of H2 to NH3 in moles, equal to b/c
all you have to do is convert 10kg of ammonia to moles.