`[X] + H_(2)SO_(4) rarr [Y]` colourless gas with irritating smell `[Y] + H_(2)SO_(4) + K_(2)Cr_(2)O_(7) rarr` Green solution `[X]` and`[Y]` are

Options

A. `SO_(3)^(2-),SO_(2)`
B. `CI^(Theta),HCI`
C. `S^(2-),H_(2)S`
D. `CO_(3)^(2-),CO_(2)`

Answer

a

Explanation

`[X]+ H_(2)SO_(4) rarr [Y]` colourless gas with irritating smell `[Y] + H_(2)SO_(4) rarr `Green solution
Sulphite ions give sulphide dioxide gas with sulpharic acid which turn acidified potassium dichromate to green
`SO_(3)^(2-) + H_(2)SO_(4) rarr SO_(2) + H_(2)O + SO_(4)^(2-)`
`3SO_(2) + K_(2)Cr_(2)O_(7) + H_(2)SO_(4) rarr K_(2)SO_(4) + underset(Green)((Cr_(2)(SO_(4))_(3))) + H_(2)O`