### 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

equation:

**Answer:**

* NaPO4 + CaCl2 → Ca(PO4)2 + NaCl*