For`He^(Theta)` and `Li^(2+)` , the energies are relased to the quantum number n through an expression
`E_(n) = (Z^(2)B)/(n^(2))` where Z is the atomic number species and `B = 2.179 xx 10^(-19) J`
a.What is the energy of the lowest level of a `He^(Theta)` ion ?
b. .What is the energy of the third level of a `Li^(2+)` ion ?

Explanation

`E_(1)` for `He^(o+) = - (2^(2) xx2.179 xx 10^(-18))/(1^(2))`
`= - 8.716 xx 10^(-18) J`
b. `E_(3)` = for `LI^(2+) = - (3^(2)xx2.179 xx 10^(-18))/(3^(2))`
`= - 2.179 xx 10^(-18) J`