National 5; Balanced equations Calculating percentage composition. Chemical equations must be balanced so that the quantities of reactants and products match. For an equation to be balanced there ...

The equation shows that 1 mol of HCl reacts with 1 mol of NaOH. So the amount of NaOH in 20.0 cm 3 is 0.025 mol. Substituting into the equation to find the concentration of NaOH: ...