Compared with ethoxide, (CH3)3C-O- is

a stronger base but a poorer nucleophile, because of steric hindrance

an equally strong base but a better nucleophile because it is larger

a stronger base and a better nucleophile

a stronger base but a poorer nucleophile, because of steric hindrance

a weaker base and a poorer nucleophile

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JEE Main levelSingle correct optionDifficulty 2 of 3o1021

Compared with ethoxide, $(CH X_{3}) X_{3} C - O X^{-}$ is

Aan equally strong base but a better nucleophile because it is larger
Ba stronger base and a better nucleophile
Ca stronger base but a poorer nucleophile, because of steric hindrance
Da weaker base and a poorer nucleophile

Answer: C

Tert-butanol (pKa about 17) is less acidic than ethanol (pKa about 16), so tert-butoxide is the stronger base. Its three methyl groups shield the oxygen, so it attacks a carbon centre slowly. Basicity is an attack on a small proton and is insensitive to bulk, whereas nucleophilicity is not.

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Compared with ethoxide, (CHX3​)X3​C−OX− is

Answer: C

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Compared with ethoxide, $(CH X_{3}) X_{3} C - O X^{-}$ is