Surface Chemistry

The correct option is (A) : Polar at outer surface but non polar at inner surface.

An assembly of surfactant molecules scattered in a liquid colloid is known as a micelle. Polar head groups,which typically make up the micelle's exterior surface, are present in micelles. Because they are polar, they face the ocean. Since they are non-polar, the hydrophobic tails are within and away from the water.

Colloid Type:
Fog is an example of an aerosol, which is a type of colloidal system where a liquid is dispersed in a gas.

In fog:

• The dispersed phase is liquid water droplets.
• The dispersion medium is air (gas).

Hence, it is a colloid of liquid in gas.

Correct Answer:

The question asks which statement is incorrect about enzymes. Let's examine each option:

1. Enzymes are biocatalysts. This is true. Enzymes accelerate chemical reactions in biological systems.

2. Like chemical catalysts, enzymes reduce the activation energy of bio processes. This is also true. Enzymes lower the activation energy needed for reactions, thus increasing the rate of the reactions without being consumed.

3. Enzymes are polysaccharides. This is incorrect. Enzymes are proteins, not polysaccharides. They are typically complex globular proteins comprising one or more polypeptide chains.

4. Enzymes are very specific for a particular reaction and substrate. True. Enzymes exhibit specificity, meaning they are selective about the substrate they bind to and the reaction they catalyze.

Hence, the incorrect statement is that enzymes are polysaccharides.

To resolve the problem, we must evaluate the flocculating power of ions and salts based on their nature and the charge present. This involves understanding concepts related to the coagulation of sols in colloidal chemistry.

Statement I Analysis: In the coagulation of a negative sol, it is a well-established fact that the flocculating power of ions increases with an increase in charge. This follows from Hardy-Schulze rule, which states that the greater the charge on the flocculating ion, the greater its capacity to cause precipitation of the sol. Thus, the order of flocculating power given is correct: Al³⁺ (3+ charge) > Ba²⁺ (2+ charge) > Na⁺ (1+ charge).

Conclusion for Statement I: This statement is correct.

Statement II Analysis: In the coagulation of a positive sol, the flocculating ability of salts is again assessed based on the valency of the anions they provide. According to the Hardy-Schulze rule, higher valency anions have higher coagulation power. NaCl provides Cl^- ions, Na₂SO₄ provides SO₄^2- ions, and Na₃PO₄ provides PO₄^3- ions. Thus, logically, the order should actually be: PO₄^3- > SO₄^2- > Cl^-, which contradicts the given statement.

Conclusion for Statement II: This statement is incorrect.

Final Answer: Statement I is correct but Statement II is incorrect.