Table of contents

Input interpretation

(NH4)3PO4 H2O + NH3 + HPO3

water ammonia metaphosphoric acid

Balanced equation

Balance the chemical equation algebraically:

(NH4)3PO4 H2O + NH3 + HPO3

Add stoichiometric coefficients, c, to the reactants and products:

C1 (NH4)3PO4 C2 H2O + C3 NH3 + C4 HPO3

Set the number of atoms in the reactants equal to the number of atoms in the products for N, H, P and O:

N: 3c1 = c3

H: 12c1 = 2c2 + 3c3 + c4

P: c1 = c4

O: 4c1 = c2 + 3 c4

Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c1 = 1 and solve the system of equations for the remaining coefficients:


c2 = 1

c3 = 3


Substitute the coefficients into the chemical reaction to



(NH4)3PO4 H2O + NH3 + HPO3