JEE Main20205 Sep 2020Morning ShiftChemistryStructure of AtomActual
The difference between the radii of 3 rd and 4 th orbits of L i 2 + is ΔR 1 . The difference between the radii of 3 rd and 4 th orbits of He + Δ R 2 . Ratio Δ R 1 : Δ R 2 is :
Options
- A8 : 3
- B3 : 8
- C2 :   3
- D3 :   2
Correct answer
C. 2 :   3
Step-by-step solution
r = 0 . 529 n 2 7 A For Li 2 + r L 2 + n = 4 - r L 2 + n = 3 = 0 . 529 3 [ 16 - 9 ] = Δ R 1 For He + r He + n = 4 - r He + n = 3 = 0 . 529 2 [ 16 - 9 ] = Δ R 2 ΔR 1 ΔR 2 = 2 3