Question

EXPLAIN LOW SOLUBILITY OF LiF and CsI IN WATER

Answer 1

Low solubility of LiF is due to its lattice enthalpy

For being soluble,lattice enthalpy should be less compared to its hydration enthalpy
But in LiF,due to small size of LiF its lattice enthalpy is higher than that of hydration enthalpy

So,LiF has low solubility.

In CsI, the larger sizes of both Cs and I are responsible for low solubility and have lesser hydration enthalpy.