JAMB - Chemistry (2010 - No. 25)
In which of the following is the entropy change positive?
Thermal dissociation of ammonium chloride
Reaction between an acid and a base
Addition of concentrated acid to water
Dissolution of sodium metal in water
Explanation
Thermal dissociation of ammonium chloride is an endothermic reaction as heat is absorbed for a positive entropy, with more products than reactants.