The energy and radius of electron present in second orbit of `He^+` respectively are

Options

A. `- 1.09 xx 10^(-18) J, 105 .8 p m `
B. `- 8.72 xx 10^(-18) J, 211.6 p m `
C. `- 4 . 36 xx 10 ^(-18) J, 52.9 p m `
D. `- 2 .18 xx 10^(-18) J, 105 . 8 p m `

Answer

D

Explanation

For `He^(+)` : Z = 2
`n = 2 , r_(n) = 52.9 xx (n^(2))/(Z) p m `
`E_(n) = - 2.18 xx 10^(-18) (Z^(2))/(n^(2)) J`
`:. E_(n) = - 2.18 xx 10^(-18)xx (4)/(4)`
`= - 2 . 18 xx 10 ^(-18) J`
`r_(n) = 52.9 xx (4)/(2)`
= 105.8 Pm