Question

An alkene $X$ is obtained by dehydration of an alcohol $Y$. $X$ on ozonolysis gives two molecules of ethanol for every molecule of the alkene. $X$ and $Y$ are:

• A. $X=3-$ hexane, $Y=$ hexanol
• B. $X=2-$ butene, $Y=2-$ butanol
• C. $X=1-$ butene, $Y=1-$ butanol
• D. $X=1-$ hexane, $Y=1-$ hexanol

Answer 1

The correct option is B $X=2-$ butene, $Y=2-$ butanol

Since on ozonolysis, $X$ gives two molecules of ethanal for every molecules of it.

$\therefore C{H}_3-\stackrel{\underset{|}{H}}{C}=O+O=\stackrel{\underset{|}{H}}{C}-C{H}_3⟶\underset{2-Butene}{C{H}_3-\stackrel{\underset{|}{H}}{C}=\stackrel{\underset{|}{H}}{C}-H_{3}C}$

Thus $X$ is 2-butene.

2-Butene is obtained by dehydration of 2-Butanol

$C{H}_{3}C{H}_2-\underset{\stackrel{|}{OH}}{CH}-C{H}_3\stackrel{-H_{2}O}{\to }C{H}_3-CH=CH-C{H}_3$

Thus, $Y$ is 2-butanol.