`LiF` a least soluble among the fluorides of alkali metals, because

Options

A. smaller size `Li` impart significant covalent character in `LiF`
B. the hydration energies of `Li^(+)` and `F^(-)` are quit higher
C. lattice energy of `LiF` is quite higher due to the smaller size of `Li^(+) and F^(-)`
D. `LiF` has strong polymeric network in solid

Answer

C

Explanation

The small size of both `Li^(+)` and `F` ion leads to a very high value of lattice energy and thus crystale of `LiF` is very diffcult to break .