Which of the following is isoelectronic pair ?

Options

A. `ICl_2 , ClO_2`
B. `BrO_2^- , BrF_2^+`
C. `ClO_2 , BrF`
D. `CN^(-) , O_3`

Answer

B

Explanation

Isoelectronic species are the species that possess the same number of total electrons. The number of electrons in each of the species is calculated as shown below:
`Icl_2 = 53 + (2 xx 17) = 87`
`ClO_2 = 17 + (2 xx 8) = 33`
`BrO_2^(-) = 35 + (2 xx 8) + 1 = 52`
`BrF_2^(+) = 35 + (2 xx 9) - 1 = 52`
`BrF = 35 + 9 = 44 `
`CN^(-) = 6 + 7 + 1 = 14`
`O_3 = 3 xx 8 = 24`
The ions `BrO_2^(-)` and `BrF_2^+` possess the same number of electrons. Therefore, the pair `BrO_2^(-)`, `BrF_2^+` is isoelectronic