Among the four halides (CH3)3C-X with X = F, Cl, Br, I, the fastest SN1 hydrolysis is shown by

MolSynapse / Question bank / Organic Reaction Mechanisms III: Nucleophilic Substitution / SN1 vs SN2: substrate, nucleophile, solvent, leaving group

NEET levelSingle correct optionDifficulty 1 of 3o3005

Among the four halides $(CH X_{3}) X_{3} C - X$ with $X$ = F, Cl, Br, I, the fastest SN1 hydrolysis is shown by

A $(CH X_{3}) X_{3} C - F$
B $(CH X_{3}) X_{3} C - I$
C $(CH X_{3}) X_{3} C - Cl$
D $(CH X_{3}) X_{3} C - Br$

Answer: B

The C-X bond is broken in the slow step, so the better the leaving group the faster the reaction. Leaving ability follows the stability (weak basicity) of the halide ion:

I X^{-} > Br X^{-} > Cl X^{-} > F X^{-}

. Hence the iodide reacts fastest.

Practice Organic Reaction Mechanisms III: Nucleophilic Substitution More on SN1 vs SN2: substrate, nucleophile, solvent, leaving group

Previous questionNext question

Among the four halides (CHX3​)X3​C−X with X = F, Cl, Br, I, the fastest SN1 hydrolysis is shown by

Answer: B

More questions on SN1 vs SN2: substrate, nucleophile, solvent, leaving group

Among the four halides $(CH X_{3}) X_{3} C - X$ with $X$ = F, Cl, Br, I, the fastest SN1 hydrolysis is shown by