Question

Lattice energy of alkali metal chlorides follows the order :

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

Answer 1

Answer: (A)

$LiCl>NaCl>KCl>RbCl>CsCl$

Answer 2

Lattice energy depends on the size of ion and it decreases with increase in size.
$\because$ The size of alkali metals increases from $Li$ to $Cs$.
$\therefore$ Lattice energy of alkali metal halides is as follows:
$LiCl > NaCl > KCl > RbCl > CsCl$