The reaction shows a Grignard reagent (RMgBr) reacting with CO₂, followed by acid hydrolysis. This is the Grignard carboxylation reaction. The Grignard reagent acts as a nucleophile, attacking the electrophilic carbon in CO₂. This forms a magnesium carboxylate salt. Subsequent acid hydrolysis (H₃O⁺) protonates the salt, yielding a carboxylic acid. The general reaction is:

$RMgBr+C{O}_2\to RCO{O}_{2}MgBr\underset{H_3{O}^{+}}{\to }RCOOH$

Therefore, the final product is a carboxylic acid with one more carbon atom than the original alkyl halide used to make the Grignard reagent.

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