The correct option for the first ionisation enthalpy (in kJ mol -1 ) of Li, Na , K and Cs respectively is

Question

The correct option for the first ionisation enthalpy (in kJ mol -1 ) of Li, Na , K and Cs respectively is (A) 496,520,419,374 (B) 374,419,496,520 (C) 520,496,419,374 (D) 374,419,520,496

Tardigrade Admin · Accepted Answer

First ionisation enthalpy increase with smaller size. Li is smallest. So, Li has highest first ionisation enthalpy. Li > Na > K > Cs

Q. The correct option for the first ionisation enthalpy (in $k J m o l^{- 1})$ of $L i$ , $N a, K$ and $C s$ respectively is

496,520,419,374

374,419,496,520

520,496,419,374

374,419,520,496

First ionisation enthalpy increase with smaller size. Li is smallest. So, Li has highest first ionisation enthalpy.

$L i > N a > K > C s$

Q. The correct option for the first ionisation enthalpy (in kJmol−1) of Li, Na,K and Cs respectively is