Discussion Forum



1)

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

Answer:

Option C

Explanation:

 First ionisation enthalpy increases with smaller size. Li is the smallest. so  Li has the highest first ionisation enthalpy

Li > Na> K> Cs