Concept:Grignard reagents react with carbon dioxide to form carboxylic acids.
Explanation:Here,
CH3CH2MgBr is ethylmagnesium bromide, a Grignard reagent.
Dry ice is solid
CO2, and dry ether provides an anhydrous medium for the reaction.
The nucleophilic carbon atom of the Grignard reagent attacks the electrophilic carbon atom of
CO2.
This forms the magnesium salt of the carboxylic acid.
On adding dilute
HCl, acid hydrolysis gives the free carboxylic acid.
The reaction can be written as:
CH3CH2MgBr+CO2→CH3CH2COOMgBrCH3CH2COOMgBr+HCl→CH3CH2COOH+MgBrClThe product contains three carbon atoms, so it is propanoic acid.
Answer:Propanoic acid (Option B).
