Question

Based on lattice energy and other considerations which one of the following alkali metal chlorides is expected to have the highest melting point ?

• A. $RbCl$
• B. $KCl$
• C. $NaCl$
• D. $LiCl$

Answer 1

The correct option is C $NaCl$

$LiCl$ has partly covalent character. Other halides are ionic in nature. Lattice energy decreases with increase of ionic radius of cation, anion being the same. Larger is the lattice energy, the higher will be melting point hence $NaCl$ will have highest melting point.