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NEET levelSingle correct optionDifficulty 1 of 3o4174

The ease of acid-catalysed dehydration of alcohols follows the order:

A $3^{\circ} > 2^{\circ} > 1^{\circ}$
B $1^{\circ} > 2^{\circ} > 3^{\circ}$
C $2^{\circ} > 3^{\circ} > 1^{\circ}$
D $1^{\circ} = 2^{\circ} = 3^{\circ}$

Answer: A

The rate-determining step is formation of the carbocation (or a transition state with carbocation character) from the protonated alcohol. Stability

3^{\circ} > 2^{\circ} > 1^{\circ}

therefore sets the dehydration order.

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