Question

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

Answer 1

The smallest size of $L{i}^{+}$ ion among all alkali metals and its high polarising power are the two factors which develop covalent character in the lithium compounds (Fajan's rule).
Compounds of other alkali metal are ionic in nature. So, they are soluble in water.
Since lithium compounds being relatively covalent are soluble in alcohol and other organic solvents in accordance with "like dissolve like."