Question

Ionisation energy of He⁺ is 19.6×10^-18J atom^-1. The energy of the first stationary state (n = 1) of Li²⁺ is

(1)8.82×10^-17 J atom^-1

(2) 4.41×10^-16 J atom^-1

(3) -4.41×10^-17 J atom^-1

(4) -2.2×10^-15 J atom^-1

Answer 1

(3) -4.41×10^-17 J atom^-1 

 

Given I.E = 19.6×10^-18

I.E ∝ z²

(I.E) Li²⁺/He⁺ = (9/4)×19.6×10^-18

= -4.41×10^-17