The compounds A and B are respectively:

Question

An egg takes 4.0 minutes to boil at sea level where boiling point of water is $T_1$ K, whereas it takes 8.0 minutes to boil on a mountain top where boiling point of water is $T_2$ K. The activation energy for the reaction that takes place during boiling of egg is

Answer 1

The reaction sequence begins with an alcohol reacting with $SOCl_2$ (thionyl chloride) and pyridine. This is followed by a reaction with $Mg$ in ether, and finally reaction with $CO_2$ and acidification. This explains the identification of compounds A and B.

Step 1: Reaction with $SOCl_2$ and Pyridine

An alcohol ($R-OH$) reacts with $SOCl_2$ and pyridine to form an alkyl chloride ($R-Cl$), with inversion of stereochemistry. Pyridine neutralizes the $HCl$ byproduct. Thus, compound A is the alkyl chloride.

Step 2: Reaction with $Mg$ in Ether

An alkyl halide (formed in step 1) reacts with magnesium ($Mg$) in dry ether to form a Grignard reagent ($R-MgX$). The Grignard reagent is a strong nucleophile and base. Therefore, compound B is a Grignard reagent.

Step 3: Reaction with $CO_2$ followed by Acidification

The Grignard reagent (compound B) reacts with carbon dioxide ($CO_2$). The Grignard reagent attacks the carbon of $CO_2$, forming a carboxylate salt, which is protonated by acidification ($H_3O^+$) to a carboxylic acid. This step isn't needed to identify A and B, but clarifies the full sequence.

Based on the starting alcohol and the reactions, A and B can be determined.

Compound A (alkyl chloride):

Compound B (Grignard reagent):

Compounds A and B are respectively:

compounds A and B

The compounds A and B are respectively:

The Correct Option is B

Solution and Explanation

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