With what neutral molecule is `ClO^(ɵ)` isoelectronic Is that molecule a Lewise Base?

Explanation

`ClO^(-)` has 17 + 8 + 1 = 26 electrons. A neutral molecule with 26 electrons is `OF_(2)` (8 + 2 `xx` 9 = 26 electrons).
Alternatively, replace `O^(-)` (9 electrons) in `ClO^(-)` by F (9 electrons). The resulting neutral molecule is ClF. Since Cl in ClF can further donate electrons to two more F atoms to form `ClF_(3)`, therefore, ClF is a Lewis base.