Q145 / 200 · MHT CET - Medical 2026 (25 April Shift 1) · Chemistry
Which of the following is Zwitter ion of sulphanilic acid?
- A
- B
- Correct answerC
- D
Solution
Sulphanilic acid is $p$-aminobenzenesulphonic acid, which contains both an acidic group ($-SO_3H$) and a basic group ($-NH_2$).
In aqueous solution or in the solid state, the acidic $-SO_3H$ group donates a proton ($H^+$) to the basic $-NH_2$ group. This internal acid-base reaction leads to the formation of a dipolar ion, known as a zwitterion.
The resulting zwitterion has a positively charged ammonium group ($-NH_3^+$) and a negatively charged sulphonate group ($-SO_3^-$) at the para positions of the benzene ring.
Looking at the given options, the structure with $-NH_3^+$ and $-SO_3^-$ at para positions represents the zwitterion of sulphanilic acid.
Answer:
In aqueous solution or in the solid state, the acidic $-SO_3H$ group donates a proton ($H^+$) to the basic $-NH_2$ group. This internal acid-base reaction leads to the formation of a dipolar ion, known as a zwitterion.
The resulting zwitterion has a positively charged ammonium group ($-NH_3^+$) and a negatively charged sulphonate group ($-SO_3^-$) at the para positions of the benzene ring.
Looking at the given options, the structure with $-NH_3^+$ and $-SO_3^-$ at para positions represents the zwitterion of sulphanilic acid.
Answer:
Hence, the correct answer is option: 'C'.