Question

Identify $A$ and $B$ in the following reaction $CH _{3}- CH _{3} \stackrel{B}{\leftarrow}{B} CH _{3} COOH \xrightarrow{A} CH _{3} CH _{2} OH$

• A. $A \rightarrow H I+$ red $P, B \rightarrow L i A l H_{4}$
• B. $A \rightarrow N V / \Delta H I+$ red $P,B \rightarrow LiAlH _{4}$
• C. $A \rightarrow L i A I H_{4} H I+$ red $P, B \rightarrow H I+$ red $P$
• D. $A \rightarrow P d-B a S O_{4} H I+$ red $P, B \rightarrow Z n +H C l$

Answer 1

Answer: (C)

$A \rightarrow L i A I H_{4} H I+$ red $P, B \rightarrow H I+$ red $P$

Answer 2

Acetic acid on reduction with lithium aluminiumhydride $(LiAIH_4)$ gives ethyl alcohol while on reduction with $HI$ and red $P$ gives
ethane

Hence, reagent $A$ and $B$ are respectively $LiAlH_{4}$ and $Hi / red P$.