Question

Ammonium phosphate NH43PO4 is an important ingredient in many fertilizers. It can be made by reacting phosphoric acid H3PO4 with ammonia NH3.

What mass of ammonium phosphate is produced by the reaction of 5.3g of ammonia?

Answer 1

$3NH_3+H_3PO_4\to(NH_4)_3PO_4$

Number of moles of ammonia$=mass/molarmass=5.3/17.031=0.3112$

Mole ratio $NH_3:(NH_4)_3PO_4=3:1$

moles of $(NH_4)_3PO_4=0.3112/3=0.1037moles$

Mass of ammonium phosphate produced=number of moles $\times$ molar mass=$0.1037\times 149.08=15.46g$