Write the electronic configurations and calculate the bond orders of `H_(2)^(+) , H_2` and `He_2` Why the bond length in `H_(2)^(+)` is longer than that in `H_2` ?

Explanation

The bond length in `H_(2)^(+)` is longer than in `H_2` because in `H_(2)^(+)` only one electron is present to shield the two nuclei from mutual repulsion. In `H_2` there are two electrons to hold the two nuclei, thus the nuclear repulsion is less than that in `H_(2) ^(+)` Hence nuclear separation in `H_(2) ^(+)` is more than in `H_2`