0.025L * 0.75mol/L acid - 0.02795L * 0.5 mol/L base used to neutralize reaction mixture = moles of acid used in reaction with metal. = 4.775*10-3 moles of acid used Solution 0.025L * 0.75mol/L acid - 0.02795L * 0.5 mol/L base used to neutralize reaction mixture = moles of acid used in reaction with metal. = 4.775*10-3 moles of acid used.