Question

Which of the following will not be soluble in sodium hydrogen carbonate?

• A. 2,4,6-trinitrophenol
• B. Benzoic acid
• C. o-nitrophenol
• D. Benzenesulphonic acid

Answer 1

Answer: (C)

o-Nitrophenol will not be soluble in sodium hydrogen carbonate.
Acids stronger than $H_{2}C{O}_3$ give $C{O}_2$ gas with sodium hydrogen carbonate and also soluble in it.
$2,4,6$-trinitrophenol, Benzoic acid and Benzenesulphonic acid stronger acids than $H_{2}C{O}_3$.
They react with sodium hydrogen carbonate to form water-soluble sodium salts.
o-Nitrophenol is a weaker acid than $H_{2}C{O}_3$. It does not react with sodium hydrogen carbonate.