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Input interpretation

NaPO4 + CaCl2 → Ca(PO4)2 + NaCl

 Calcium chloride sodium chloride

Balanced equation

Balance the chemical equation algebraically: 

NaPO4 + CaCl2 → Ca(PO4)2 + NaCl

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

c1NaPO4 + c2CaCl2 → c3Ca(PO4)2 + c4NaCl

Set the number of atoms in the reactants equal to the number of atoms in the products for Na, P, O, Ca and Cl:

Na: c1 = c4

P: c1 = 2c3

O: 4c1 = 8c3

Ca: c2 = c3

Cl: 2c2 = 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 c2 = 1 and solve the system of equations for the remaining coefficients:

c1 = 2

c2 = 1

c3 = 1 

c4 = 2

Substitute the coefficients into the chemical reaction to obtain the balanced



NaPO4 + CaCl2 → Ca(PO4)2 + NaCl