Endothermic reaction between hydrated barium hydroxide and ammonium chloride
name: Endothermic ion-exchange reaction between solid barium hydroxide and ammonium chloride
During this reaction, the two solids form a liquid and a gas. Based on this fact, it can be assumed that the change in entropy in this case will be positive, and will help the reaction to proceed. Thus, the temperature of the reaction can be positive or negative.
The thermal effect of the reaction can be calculated based on the standard enthalpies of formation of the materials. Depending on the assumptions about the product (BaCl2 or BaCl2*H2O), it is equal to 164 or 135 kJ / mol.