Question

Statement I: In the coagulation of a negative sol, the flocculating power of the three given ions is in the order:

Al⁺³ > Ba⁺² > Na⁺

Statement II: In the coagulation of a positive sol, the flocculating power of three given salts is in the order:

NaCl > Na₂SO₄ > Na₃PO₄

In the light of above statements, choose the most appropriate answer from the options given below:

Options

• Both statement I and statement II are incorrect.

• Statement I is correct but statement II is incorrect.

• Statement I is incorrect but statement II is correct.

• Both statements I and II are correct.

Answer 1

Statement I is correct but statement II is incorrect.

Explanation:

For the coagulation of a negative sol, the flocculating power order is indeed: Al⁺³ > Ba⁺² > Na⁺, because higher charge leads to greater coagulating power.

However, in the coagulation of a positive sol, the order of flocculating power for anions is different; typically, it follows: [Fe(CN)₆]⁴⁻ > \[\ce{PO^{3-}4}\] > \[\ce{SO^{2-}4}\] > Cl⁻, which contradicts the given order NaCl > Na₂SO₄ > Na₃PO₄.

Therefore, Statement I is correct but Statement II is incorrect.