Select the coloured compound amongst the following (atomic no `Ti=22,Cr=24,Cu=29, Zn=30`)

Options

A. `TiCl_(4)`
B. `CrCl_(3)`
C. `ZnCl_(3)`
D. `CuCl`

Answer

B

Explanation

`""_(22)Ti =[Ar] 3d^(2) 4s^(2) implies Ti^(4+)` = [Ar]
(No unpaired electrons)
`""_(24)Cr = [Ar] 3d^(5) 4s^(1 implies Cr^(3 +) = [Ar] 3d^(3)`

(Three unpaired electrons)
`""_(30) Zn = [Ar] 3d^(10) 4s^(2) implies Zn^(2+) = [Ar] 3d^(10)`

(All electrons paired)
`""_(29)Zn = [Ar] 3d^(10) 4s^(1) implies Zn^(+) = [Ar] 3d^(10)`

(All electrons paired)
Since `Cl^(3+)` ions has 3 unpaired electrons.
therefore its salt i.e., `CrCl_(3)` will be coloured .