Which among the following will be named as dibromidobis (ethylene diamine) chromium (III) bromide?

Options

A. `[Cr(en)_3] Br_3`
B. `[Cr(en)_2 Br_2]Br`
C. `[Cr(en)Br_4]^(-)`
D. `[Cr(en)Br_2] Br`

Answer

B

Explanation

According to the rules for nomenclature, dibromido is `Br_2`, bis(ethylenediamine) is `(CH_2 NH_2 CH_2 NH_2)_2`or `(en)_2` and bromide is outside the square bracket. Let oxidation state on Cr be x, then we have
`x + 0(2) + (-1) 2= +1 = x = +3`