On passign `CI_(2)` water in a mixture of KBr and KI solution in contact with `C CI_(4)` continuously with occasional shakinh, we observe

Options

A. Orange `C CI_(4)` layer changing to violet
B. Persisting violet `C CI_(4)` layer
C. Persisting brown layer
D. Violet layer changing into brown and finally colourless

Answer

D

Explanation

`CI_(2)+2I^(Theta)rarr 2CI+I_(2)Theta`
`CI_(2)+2Br^(Theta)rarr Br_(2)+2CI^(Theta)`
Oxidising agent: `CI_(2)gtBr_(2)I_(2)`
Hence, `CI_(2)` oxidises `I^(Theta)` first to `I_(2)` which gives violet colour in `C CI_(4)`, then `Br_(2)^(Theta)rarr Br_(3)`, which gives bron colour in `C CI_(4)`, finally `I_(2)` is oxidised to `IO^(Theta)`. Hence, the `C CI_(4)` layer turns colourless.