Sodium chloride reacts with phosphoric acid to form sodium phosphate and hydrochloric acid. Answer in a balanced chemical equation.

  3NaCl   +    H₃PO₄  →    Na₃PO₄   +  3HCl

Explanation:

The reactants in this reaction are:

       Sodium chloride  -    NaCl

        Phosphoric acid   -  H₃PO₄

Products of the reaction:

        Sodium phosphate  - Na₃PO₄

         Hydrochloric acid    - HCl

Therefore;

            NaCl   +    H₃PO₄  →    Na₃PO₄   +  HCl

To balance this reaction expression, assign variables a,b, c and d to it;

   aNaCl   +    bH₃PO₄  →    cNa₃PO₄   +  dHCl

Conserving Na;  a  = 3c

                    Cl;   a  = d

                     H;   3b  = d

                     P;   b  = c

                    O;   4b  = 4c

let c  = 1, b  = 1, a  = 3 and d = 3

So;

      3NaCl   +    H₃PO₄  →    Na₃PO₄   +  3HCl