Question

The functional groups that are responsible for the ion-exchange property of cation and anion exchange resins, respectively, are

• A. $–{\mathrm{SO}}_3\mathrm{H}\mathrm{and}–\mathrm{COOH}$
• B. $–{\mathrm{SO}}_3\mathrm{H}\mathrm{and}–{\mathrm{NH}}_2$
• C. $–{\mathrm{NH}}_2\mathrm{and}–{\mathrm{SO}}_3\mathrm{H}$
• D. $–{\mathrm{NH}}_2\mathrm{and}–\mathrm{COOH}$

Answer 1

The correct option is B

$–{\mathrm{SO}}_3\mathrm{H}\mathrm{and}–{\mathrm{NH}}_2$

The correct answer is (B)

The Explanation for the correct option:

(B)

• Explanation: This effect is weaker than the inductive effect of electrons from the benzene ring. Because the S atom is larger than the C atom, their p-orbitals cannot overlap as well as the C atom's in the benzene ring.
• There are two primary categories of ion exchange resins: cation exchange resins, which exchange positively charged ions like sodium for negatively charged ions like calcium, and anion exchange resins, which exchange negatively charged ions like chloride for arsenic.
• To make a more acidic cation-exchange resin, water-insoluble styrene is used to prepare the polymer, which is then sulfonated to make it hydrophilic.

The Explanation for the incorrect option:

(A)

• Explanation: Sulfonic acids are extremely potent acids.
• P-toluenesulfonic acid is the most common sulfonic acid. Sulfonic acid is Sulfuric acid with one of the Hydroxyl groups replaced by an organic substituent.
• Sulfonate anions are the conjugate bases of sulfonic acids. Sulfonic acid is sulfuric acid with one of the Hydroxyl groups replaced by an organic substituent.
• Sulfonate anions are sulfonic acid conjugate bases that are resonance stabilized. As a result, sulfonate anions make excellent leaving groups.

(C)

• Explanation: It can be used to catalyze the esterification reaction of carboxylic acids with equimolar amounts of acid-sensitive and sterically demanding alcohols.
• By heating a mixture of D-glucose, p-toluenesulfonic acid, and diphenyl ammonium tosylate, a novel Carbon-based solid acid was easily prepared.

(D)

• Explanation: Proteins are composed of smaller units known as amino acids. The name amino acid refers to the fact that each contains an amino and a carboxylic acid.
• Amino acids are organic molecules with an Amine functional group$(-{\mathrm{NH}}_2)$ and a Carboxylic Acid$(-\mathrm{COOH})$. functional group.

Hence, the correct answer is (B): In addition to the inductive effect of electrons from the benzene ring, this effect is weaker.