Give the formulae of the species that will be isoelectronic with the following atoms or ions :
`Cl^-`

Explanation

Give the formulae of the species that will isoelectronic with the following atoms or ions:
`Cl^(-)`: `Cl^(-)` ion contains 18 electrons. The species isoelectronic with `Cl^(-)` ions are: `P^(3-), S^(2-), Ar, K^(+), Ca^(2+), Sc^(3+)` etc.