In the $S_{N} 1$ hydrolysis of $(CH X_{3}) X_{3} C - Br$ the rate-determining step is ionisation. The transition state of this step is best described as

Asymmetrical, with the C-Br bond fully intact
Bclose to the product alcohol
Cclose to $(CH X_{3}) X_{3} C - Br$ in structure, because the step is exothermic
Dclose to the carbocation (ion pair) in structure, because the step is strongly endothermic

Answer: D

Formation of

(CH X_{3}) X_{3} C X^{+}

and

Br X^{-}

from the neutral halide is endothermic. By the Hammond postulate the transition state is late and resembles the carbocation ion pair. For this reason features that stabilise the cation, such as extra alkyl groups, also lower the barrier.

Practice General Organic Chemistry III: Reaction Intermediates More on Hammond postulate and reactivity-selectivity

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In the SN​1 hydrolysis of (CHX3​)X3​C−Br the rate-determining step is ionisation. The transition state of this step is best described as

Answer: D

More questions on Hammond postulate and reactivity-selectivity

In the $S_{N} 1$ hydrolysis of $(CH X_{3}) X_{3} C - Br$ the rate-determining step is ionisation. The transition state of this step is best described as