The lattice enthalpy and hydration enthalpy of four compounds are given below:

the pair of compounds which is soluble in water is:

How is lattice enthalpy related to stability of an ionic compound?

Lattice enthalpy of an ionic compound depends upon

Given The enthalpy of hydrogenation of these compound will be in

The solubility of a crystalline compound in water is influenced by two factors. These are lattice enthalpy and hydration enthalpy. Lattice enthalpy is needed to separate the ions from the crystal lattice. At the same time hydration enthalpy is released when the ion are dissolved in water. The resultant of these two opposing tendencies guides the solubility of the compound in water. If lattice enthalpy has a greater magnitude, the compound has low solubility. In case hydration enthalpy is more, then the compound is highly soluble in water. The hydroxide which is maximum soluble in water is :