Thermochemical Approaches to Neutralization Reaction between Weak Acid and Strong Base

As an advanced laboratory activity at high school, thermochemical approaches to neutralization reactions between weak acids and strong base are proposed. For the reactions of organic acids and sodium hydroxide in aqueous media, the total enthalpy change ∆Htotal can be determined by means of calorimetry using a thermometer with a thermistor sensor. For determining the dissociation enthalpy ∆dH of the weak acid, a simple procedure of measuring the acid dissociation constant Ka at different temperatures was developed. Using the experimental values of ∆Htotal and ∆dH, students can study the thermochemical relation for the neutralization between weak acid and strong base. The practical usefulness of the present laboratory activity as an advanced thermochemical experiment at high school and as an introductory experiment to chemical thermodynamics at college was discussed.