Introduction to Titration Calorimetry

Abstract

Titration calorimetry is a relatively rapid way of obtaining thermodynamic data on reactions in solution. Enthalpy changes for solution of solids, for sorption of solutes on suspensions of sorbents, for reactions of gases with solutes, and for mixing of liquids and solutions can all be done in calorimeters equipped to handle gases, liquids, and solids, e.g., see Russell et al. (2006). However, this brief is largely limited to consideration of methods involving titration of a solution of one reactant into a solution of a second reactant. Titration calorimetry has three applications, analytical determinations of concentrations of reactants in solution, determination of enthalpy changes for reactions in solution, and under certain conditions, simultaneous determination of equilibrium constants and enthalpy changes for reactions in solution. This last application provides a full complement of thermodynamics for reactions in solution, i.e., the Gibbs energy change (Δ_rG = −RTlnK), the enthalpy change (Δ_rH), and the entropy change (Δ_rS = (Δ_rH − Δ_rG)/T); R is the gas constant, and T is the Kelvin temperature.