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Which of the following undergoes sn1 solvolysis in ethanol/water at the fastest rate?

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Final answer:

In an ethanol/water solvent, compounds capable of forming a stable tertiary carbocation will undergo SN1 solvolysis at the fastest rate, since the stability of the carbocation intermediate is crucial for the reaction's speed.

Step-by-step explanation:

The rate of SN1 solvolysis in a solvent like ethanol/water is influenced by the stability of the carbocation intermediate. In SN1 reactions, substrates that can form a more stable carbocation tend to react at a faster rate. Therefore, compounds with a tertiary carbon attached to the leaving group will generally undergo SN1 solvolysis more rapidly than secondary or primary substrates.

Polar protic solvents such as ethanol/water can stabilize the ionic intermediates through solvation, enhancing the dissociation of the leaving group. Since the question concerns the SN1 mechanism, where the rate-determining step is the formation of a carbocation, a tertiary alkyl halide would typically undergo SN1 solvolysis at the fastest rate. Components like a tertiary carbon next to a leaving group are ideal for promoting this process, as they lead to the formation of a stable carbocation intermediate, which is then quickly captured by the solvent acting as a nucleophile, leading to the formation of the final product.

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