Question

Acid D formed in above reaction is :

• A. Gluconic acid
• B. Succinic acid
• C. Oxalic acid
• D. Malonic acid

Answer 1

The Correct Option is B

To identify acid D in the reaction, we analyze each step:

1. Step 1: Ethyl bromide \(C_2H_5Br\) undergoes dehydrohalogenation with alcoholic KOH to form an alkene, ethylene \(C_2H_4\):
   \(C_2H_5Br \xrightarrow[]{alc.\,KOH} C_2H_4\)
2. Step 2: Ethylene \(C_2H_4\) reacts with bromine \(Br_2\) in carbon tetrachloride \(CCl_4\) to yield 1,2-dibromoethane \(BrCH_2CH_2Br\):
   \(C_2H_4 + Br_2 \xrightarrow[]{CCl_4} BrCH_2CH_2Br\)
3. Step 3: 1,2-Dibromoethane \(BrCH_2CH_2Br\) reacts with excess KCN via substitution, replacing bromine with cyanide groups to form ethylene cyanide \(NCCH_2CH_2CN\):
   \(BrCH_2CH_2Br + 2KCN \rightarrow NCCH_2CH_2CN\)
4. Step 4: Hydrolysis of ethylene cyanide \(NCCH_2CH_2CN\) with excess water and acid \(H_3O^+\) converts nitrile groups to carboxylic acid groups, forming succinic acid \(HOOCCH_2CH_2COOH\):
   \(NCCH_2CH_2CN \xrightarrow[]{H_3O^+} HOOCCH_2CH_2COOH\)

Therefore, acid D formed is Succinic acid.

The correct answer is Succinic acid.