Question

A toxic compound “A” when reacted with NaCN in aqueous acidic medium yields an edible cooking component and food preservative “B”. “B” is converted to “C” by dibromane and can be used as an additive to petrol to reduce emission. “C” upon reaction with oleum at 140°C yields an inhalable anesthetic “D”. Identify “A”, “B”, “C”, and “D”, respectively.

• A. Methanol; formaldehyde; methyl chloride; chloroform
• B. Ethanol; acetonitrile; ethylamine; ethylene
• C. Methanol; acetic acid; ethanol; diethyl ether
• D. Acetaldehyde; 2-hydroxyethane; acetic acid; propanoic acid

Hint:

Organic compound transformations depend on reactions like nucleophilic substitution and addition of reagents like dibromane and oleum.

Answer 1

The Correct Option is C

To solve this problem, we need to identify the compounds "A", "B", "C", and "D" based on the given chemical reactions and their descriptions. Let's break down the problem step-by-step:

1. Compound "A" reacts with NaCN in an aqueous acidic medium to yield "B". "B" is an edible cooking component and food preservative.
   • One common compound that reacts with NaCN to form a product used in cooking and preservation is methanol (CH₃OH), which can form acetic acid (CH₃COOH) under these conditions.
   • Thus, "A" is Methanol and "B" is Acetic Acid.
2. "B" is converted to "C" by dibromane, which can be used as an additive to petrol.
   • Acetic acid, when reacted with dibromane, can potentially form ethanol via esterification followed by reduction.
   • Ethanol is used as an additive to petrol to reduce emissions. Thus, "C" is Ethanol.
3. "C" reacts with oleum at 140°C to yield an inhalable anesthetic "D".
   • Ethanol reacting with oleum could eventually lead to the formation of diethyl ether through dehydration processes, which is a known inhalable anesthetic.
   • Therefore, "D" is Diethyl Ether.

After analyzing the reactions described and the properties of the compounds, we can conclude:

Correct Answer: Methanol; acetic acid; ethanol; diethyl ether.

Answer 2

The given question involves a series of chemical reactions that transform compound “A” into compounds “B”, “C”, and “D”. Let's identify each compound step-by-step.

1. Identify Compound “A”: 
   We start with compound “A” that reacts with NaCN in an aqueous acidic medium to yield compound “B”. The process describes the formation of acetic acid from methanol via a cyanohydrin intermediate, a reaction known as the Kharasch-Sosnovsky reaction. Thus, compound “A” is methanol.
2. Identify Compound “B”: 
   Methanol forms acetic acid upon reacting with NaCN. Acetic acid, also known as ethanoic acid, is a common edible cooking component and a food preservative. Therefore, compound “B” is acetic acid.
3. Identify Compound “C”: 
   Compound “B” (acetic acid) is then converted to compound “C” by the addition of dibromane. Dibromine addition leads to the formation of ethanol through decarboxylation. Ethanol can be used as an additive in petrol to reduce emissions. Hence, compound “C” is ethanol.
4. Identify Compound “D”: 
   Ethanol, when reacted with oleum at 140°C, forms diethyl ether, which is known as an inhalable anesthetic. Thus, compound “D” is diethyl ether.

Based on this analysis, the correct identities of compounds are:

• Compound “A” - Methanol
• Compound “B” - Acetic Acid
• Compound “C” - Ethanol
• Compound “D” - Diethyl Ether

Conclusion: The correct answer is Methanol; acetic acid; ethanol; diethyl ether.