Which of the following alkyl halides will undergo hydrolysis via the S _ N 1 mechanism at the fastest rate and yield a racemic mixture?

Step-by-step solution

For an alkyl halide to yield a racemic mixture upon S _ N 1 hydrolysis, the starting compound must be chiral. For the reaction to occur at the fastest rate, it should form the most stable carbocation (e.g., a tertiary carbocation). 2-Bromo-2-methylbutane is a tertiary alkyl halide but it is achiral (the carbon bearing the bromine atom is attached to two identical methyl groups). It will undergo S _ N 1 fast but cannot yield a racemic mixture as it is not optically active. 2-Bromobutane is a chiral secondary alkyl h