calculate the energy assoclated with the first orbit of `He^(+)` . What is the radius of this orbit?

Explanation

`E_(n) = - (2.18 xx 10^(-18) Z^(2))/(n^(2))J " atom"^(-1)`
For `He^(+), n = 1, Z = 2 " " :. E_(1) = - ((2.18 xx 10^(--18) J) (2^(2)))/(12) = - 8.72 xx 10^(-18) J`
Radius of H-like particles is given by `r_(n) = ((0.0529)n^(2))/(Z)nm`
For `He^(+), n = 1, Z = 2 " " :. r_(1) = (0.0529 xx 1^(2))/(2^(2)) = 0.02645 nm`