cis-1-Bromo-1,4-dimethylcyclohexane is hydrolysed in water by a pure SN1 mechanism (planar tertiary carbocation, water attacks either face). Select the correct statements.

AOnly the trans alcohol is formed because of Walden inversion.
BBoth cis- and trans-1,4-dimethylcyclohexan-1-ol are formed.
CThe product mixture is optically inactive.
DThe starting bromide is optically active.

Answer: B, C

The cation is planar at C-1 so water adds from either face, giving both diastereomeric alcohols. Both products, and the starting bromide, have a plane of symmetry through C-1 and C-4 and are achiral, so no optical activity appears.

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