An unknown compound of car bon, hydrogen and oxygen contains 69.77% carbon and 11.63% hydrogen and has a molecular weight of 86. It does not reduce Fehling solution, but forms a bisulphite addition compound and gives a positive iodoform test. How many possible structures can be drawn for the unknown compound?

An unknown compound of car bon, hydrogen and oxygen contains 69.77% ca

1.	An unknown compound of car bon, hydrogen and oxygen contains 69.77% carbon and 11.63% hydrogen and has a molecular weight of 86. It does not reduce Fehling solution, but forms a bisulphite addition compound and gives a positive iodoform test. How many possible structures can be drawn for the unknown compound?
Answer» Solution :Empirical formula can be calculated as `therefore` Empirical formula of compound is `C_5H_(10)O` and empirical formula wt. = 86. Also molecular wt. = 86. `therefore` Molecular formula of compound is `C_5H_(10)O`. (ii) Compound forms bisulphite addition compound and THUS has CARBONYL gp, i.e. aldehyde or ketone. (III) It does not reduce Fehling solution and thus it is not an aldehyde but a ketone. (iv) It gives positive iodoform test and thus it has unit, `CH_(3)-underset(O)underset(\|\|)C-` (v) Above facts REVEAL that the compound is `underset("pentan-2-one")(CH_(3)CH_(2)CH_(2)COCH_(3))` or `underset("3-methylbutan-2-one")((CH_(3))_(2)CHCOCH_(3))`