Given below are two statements: one is labelled as Assertion A and...

The low solubility of $LiF$ in water is due to its high lattice enthalpy.

The hydration enthalpies of alkali metal ions in aqueous solution decreases with increase in ionic sizes.

${Li}^{+} > {Na}^{+} > {K}^{+} > {Rb}^{+} > {Cs}^{+}$

${Li}^{+}$ has maximum degree of hydration and for this reason lithium salts are mostly hydrated, e.g., $LiCl . 2{H}_{2}O$

Hence, A is true and R is false.