Question

An alcohol 'A' on dehydration gives B which on ozonolysis gives acetone and formaldehyde.What are A and B respectively?

Answer 1

1.An alcohol A on dehydration gives B which on ozonolysis gives acetone and formaldehyde. B decolourises KMno4 solution But A does nott. A and B respectively are
A. (CH3)3COH & (CH3)2C=CH2
B. (CH3)2CHCH2OH & (CH3)2c=C

Answer:

The Answer is option B.
(CH3)2CH-CH2OH on dehydration would give (CH3)2C=CH2

And when you ozonize them the double bond breaks and Oxygen attaches itself at the loose ends

(CH3)2C=/=CH2 --> (CH3)2C=O (acetone) + O=CH2 (formaldeyhde)

compound B decolorises KMnO4 means, B is an unsaturated compound with a Double bond. It can only form if the both carbons involve in forming the double bond contribute in dehydrating a water molecule. Hence option A is not correct, as the Carbon atom is tertiary, no H attached to it, so dehydration wont be possible.