Compound A (molecular formula `C_(3)H_(8)O)`is treated with acidified potassium dichromate to form a product B (molecular formula `C_(3)H_(6)O)`. B forms shining silver mirror on warming with ammoniacal silver nitrate. B when treated with an aqueous solution of `H_(2)NCONHNH_(2)`, `HCl` and sodium acetate gives a product C. Identify the structure of C.

Options

A. `CH _ 3 CH _ 2 CH= NNHCONH _ 2 `
B. `CH _ 3 - underset ( CH_ 3) underset(|) ( C) = NNHCONH _ 2 `
C. `CH _ 3 - underset ( CH _ 3) underset ( | ) C = NCONHNH _ 2 `
D. ` CH _ 3 CH _ 2 CH = NCONHNH _ 2 `

Answer

A

Explanation

Reaction of B indicates that B is an aldehyde thus B should be `C_(2)H_(5)CHO or CH_(3)CH_(3)CH_(2)CHO` and therefore C should be `CH_(3)CH_(2)CH=NNHCONH_(2)`

`CH_(3)CH_(2)CHO+underset("semicarbazidic")(H_(2)NHCONH_(2)) to underset("semicarbazone [C]")(CH_(3)CH_(2)CH)=NNHCOOH_(2)`