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NEET levelSingle correct optionDifficulty 1 of 3g2250

Which hydrogens of the compound shown are the most acidic?

Athe CH3 hydrogens
Bthe CH2 hydrogens between the two C=O groups
Call hydrogens are equally acidic
Dnone of them, since there is no O-H

Answer: B

The compound is pentane-2,4-dione (acetylacetone). Loss of a CH2 proton gives an enolate stabilised over both carbonyls (pKa about 9). The terminal CH3 hydrogens (pKa about 20) give an enolate delocalised over only one carbonyl.

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