For each pair, the carbonyl compound that is hydrated to the greater extent in water is: (I) HCHO or CH3CHO; (II) CH3COCH3 or ClCH2COCH3; (III) CCl3CHO or CH3CHO. The correct choices (I, II, III) are

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JEE Advanced levelSingle correct optionDifficulty 3 of 3co048

For each pair, the carbonyl compound that is hydrated to the greater extent in water is: (I) $HCHO$ or $CH X_{3} CHO$ ; (II) $CH X_{3} COCH X_{3}$ or $ClCH X_{2} COCH X_{3}$ ; (III) $CCl X_{3} CHO$ or $CH X_{3} CHO$ . The correct choices (I, II, III) are

A $HCHO$ , $ClCH X_{2} COCH X_{3}$ , $CCl X_{3} CHO$
B $CH X_{3} CHO$ , $CH X_{3} COCH X_{3}$ , $CCl X_{3} CHO$
C $CH X_{3} CHO$ , $ClCH X_{2} COCH X_{3}$ , $CH X_{3} CHO$
D $HCHO$ , $CH X_{3} COCH X_{3}$ , $CH X_{3} CHO$

Answer: A

Hydration is favoured by a more electrophilic and less hindered carbonyl. Formaldehyde has no donating group, the chlorine of chloroacetone withdraws electrons, and three chlorines in chloral do so strongly. All three first members are therefore hydrated more.

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For each pair, the carbonyl compound that is hydrated to the greater extent in water is: (I) HCHO or CHX3​CHO; (II) CHX3​COCHX3​ or ClCHX2​COCHX3​; (III) CClX3​CHO or CHX3​CHO. The correct choices (I, II, III) are

Answer: A

More questions on Nucleophilic addition and addition-elimination reactions

For each pair, the carbonyl compound that is hydrated to the greater extent in water is: (I) $HCHO$ or $CH X_{3} CHO$ ; (II) $CH X_{3} COCH X_{3}$ or $ClCH X_{2} COCH X_{3}$ ; (III) $CCl X_{3} CHO$ or $CH X_{3} CHO$ . The correct choices (I, II, III) are