Question

All compounds of alkali metals are easily soluble in water but lithium compounds are more soluble in organic solvents. Explain.

Answer 1

Because of the small size, high electronegativity and high ionization enthalpy, lithium compounds have considerable covalent character while compounds of other alkali metals are ionic in nature. As a result, compounds of lithium are more soluble in organic solvents while those of other alkali metals are more soluble in water.

Answer 2

Although solubility of lithium ion is greatest because it has high heat of hydration.But when it forms compound it behaves as most covalent among 1st group it is due to polarising power of cation. higher the polrisibility higher the nature of covalent character. so when it forms mostly covalent compound. LiI is most covalent in nature