Question

The ratio between radii of `He^(+)` ion and `H` atom is
A. `1`
B. `1/2`
C. `3/2`
D. `2`

Answer 1

Correct Answer - A
Value of `Z` for hydrogen =1
Value of `Z` for helium = 2
Value of `n` for both is =1
`r_(H)= (052xx1^(2))/(1) r_(He^+)=(0.52xx1^(2))/(1)`
`(r_H)/(r_(He^+)) = 1:1 or r_(He^+):r_(H)=1:1`.