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Chemistry lab note says that:

1) Aromatic acids like benzoic acid and salicylic acid are NOT soluble in water. But they are soluble in 5% NaOH, and 5% NaHCO3.

Due to having a large hydrcarbon part (which is hydrophobic), it is understandable that aromatic acids won't dissolve in water. But why would they dissolve in base solvents.

2) aromatic carbonyl compounds like benzaldehyde and acetophenone are NOT soluble in H2O, 5%NaOH, 5% NaHCO3, 5% HCl. But they are soluble in highly concentrated H2SO4. Got no idea about the reason behind it. Can somebody clarify?

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Carboxylic acids easily react with bases forming salts, which are ionic compounds and are usually readily dissolve in polar solvents such as water, which obviously makes 95% of your base solution.

Carbonyl compounds are easily dissolved in strong sulfuric acid as 1) a reaction may take place, introducing -SO3H group to position 3 of aromatic ring of respective carbonyl compound; and 2) a strong acid can form hydrogen bonds with carbonyl oxygen. In both cases affinity of carbonyl compounds towards sulfuric acid is increased.

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