Which one of the following compounds will not be soluble in sodium bicarbonate?

o-Nitrophenol will not be soluble in sodium bicarbonate. o-Nitrophenol is a very weak acid and it does not react with sodium bicarbonate. The acidity of 2, 4, 6 - Trinitrophenol is higher and it reacts with sodium bicarbonate. Benzoic acid and Benzene sulphonic acid are stronger acids and they also react with sodium bicarbonate. Thus 2, 4, 6 - Trinitrophenol, Benzoic acid and Benzene sulphonic acid are soluble in sodium bicarbonate. C6H5COOH + NaHCO3 → NaC6H5COO + H2O(l) + CO2(g) C6H5SO2OH + NaHCO3 → C6H5SO2ONa + H2O + CO2