Question

$C{H}_{3}C{H}_{2}OH\underset{\text{step}-1}{\overset{C{l}_2}{\to }}C{H}_{3}CHO\underset{\text{step}-2}{\overset{3C{l}_2}{\to }}C{l}_{3}CCHO$
In above reactions the role of $C{l}_2$ in step-1 and step-2 respectively is :

• A. oxidation, chlorination
• B. reduction, chlorination
• C. oxidation, addition
• D. reduction, substitution

Answer 1

Answer: (A)

$C{H}_{3}C{H}_{2}OH\underset{\text{step}-1}{\overset{C{l}_2}{\to }}C{H}_{3}CHO$
The above reaction is an example of oxidation. Due to oxidation $-C{H}_{2}OH$ group is oxidised to $-CHO$ group.
$C{H}_{3}CHO\underset{\text{step}-2}{\overset{3C{l}_2}{\to }}C{l}_3\cdot C\cdot CHO$
In the second step chlorination takes place. In chlorination hydrogen atom changes by chlorine.