To balance the chemical equation for the reaction between sodium hydroxide NaOH and hydrochloric acid HCl to produce sodium chloride NaCl and water H2O , we need to make sure that the number of atoms of each element is the same on both sides of the equation.Here's the unbalanced equation:NaOH + HCl NaCl + H2ONow, let's balance the equation:1. There is 1 Na atom on both sides, so it is already balanced.2. There is 1 O atom on both sides, so it is already balanced.3. There are 2 H atoms on the left side 1 from NaOH and 1 from HCl and 2 H atoms on the right side 2 from H2O , so it is already balanced.4. There is 1 Cl atom on both sides, so it is already balanced.Since all the elements are balanced, the balanced chemical equation is:NaOH + HCl NaCl + H2O