In which of the following pairs of molecules/ions, botht hes pecies are not likely to exist-

Options

A. `H_(2)^(+),He_(2)^(2-)`
B. `H_(2)^(-),He_(2)^(2-)`
C. `H_(2)^(2+),He_(2)`
D. `H_(2)^(-),Fe_(2)^(2+)`

Answer

C

Explanation

`H_(2)^(2+):(sigma_(1s))^(0)`
`He_(2):(sigma_(1s))^(2)(sigma_(1s)^(**))^(2)`

Species with bond order zero does ot exist. Hence, `H_(2)^(2+)` and `He_(2)` does not exist.