All compounds of alkali metals are easily soluble in water

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

Exceptionally small size of Li+ion and high polarising power, these are the two factors which develops covalent character in the lithium compounds (Fajan’s rule). Compounds of other alkali metals are ionic in nature. So, they are soluble in water, while lithium compounds being relatively covalent are soluble in alcohol and other organic solvents.