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(c) colloidal particles have negative charge.

Enzymes are complex nitrogeneous organic compounds produced by living cells which catalyze the biochemical reactions occurring living organism. Enzyme catalysis works on enzyme-substrate binding. This phenomenon is proposed by Michaelis and Menten.

Adsorption is accompanied by decrease in enthalpy and decrease in entropy.

At lower concentration soap forms a normal electrolytic solution with water. After a certain concentration called critical micelle concentration, colloidal solution is formed.

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Surface chemistry is referred to as the study of the phenomenon occurring on the surfaces of substances. This is very applicable in industries and day-to-day lives. In other words, surface chemistry deals with all types of surface phenomenon.There are various phenomena taking place on the surface of substances and some of them are:

• Adsorption
• Heterogeneous Catalysis
• Corrosion
• Crystallization

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Dispersion medium - Liquid/water; Dispersed phase -Liquid /oil.

Dispersed phase-liquid/water ; Dispersed medium -liquid /oil.

Dispersed phase: liquid;

Dispersion medium : liquid,liquid fat dispersed in water.

Gel eg. cheese, butter, jellies. 

Sol is a colloidal suspension with solid particles in a liquid.

 example -paints, cell fluids

(a)  3 1 4 2

The intensity of color in the solution decreases because the dye gets adsorbed on the surface of carbon.

Maltose. 

It is a carbohydrate whereas others are enzyme catalysts.

Zeolites are called shape selective catalysts because their catalytic action depends upon the size and shape of the reactant and the product molecules as well as on their own pores and cavities.

A colloidal sol. of ferric hydroxide can be prepared by adding small quantity of ferric chloride solution to freshly prepared precipitate of ferric hydroxide. 

(a) Both A and R are correct and R is the correct explanation of A.

Glucose + zymase →  ethyl alcohol.

Correct answer is a) iv) Gel

Adsorption would occur where silica gel is kept in the vessel where as absorption will occur in the corner where CaCl₂ is placed.

(c) Charcoal

Ammonia is called adsorbate.

Pearls is an example for solid sol.

Silica gel is usually adsorb Water

(c) Coloured glass

(c) Robert Brown

Cheese is an example of gel

(b) Brownian movement

Adsorption is a surface phenomenon in which a  substance gets accumulated on the surface of the solid rather than in the bulk of a solid or liquid. The surface that adsorbs is called adsorbent and the one that gets absorbed a called an adsorbate. For example, it can adsorb large amount of hydrogen gas.

Detailed Answer:

The answer is (a)

Four differences between physical adsorption and chemical adsorption:

(c) Ion exchange resin

(b) Silica gel

It is a graph which shows relationship between the quality of gas adsorbed by unit mass of solid adsorbent and pressure at a particular temperature. 

x/m = kp1/n

Charcoal is used during world war as gas masks

In order to adsorb poisonous gases. The principle involved is adsorption.

(a) Hydration

(a) Both A and R are correct and R is the correct explanation of A.

(b) (ii) & (iii)

A minimum of 6.6mL of AB is required to coagulate the sol. The moles of AB in the sol is
\(\frac{6.6\times0.01}{20}\) = 0.033 moles 

This means that a minimum of 0.033 moles or 0.0033 x 1000 = 3.3 milli moles are required for coagulating one litre of sol. Flocculation value of AB for X = 3.3

(c) shortens the time to reach equilibrium

(d) enthalpy of adsorption is low and positive

(c) It requires activation energy

(b) K₄[Fe(CN)₆] 

The flocculation and setting down of the sol particles is called coagulation. 

Various method of coagulation are given below: 

1. Addition of electrolytes 

2. Electrophoresis

3. Mining oppositively charged sols 

4. Boiling.

Addition of electrolytes 

A negative ion causes the precipitation of positively charged sol and vice versa. When the valency of ion is high, the precipitation power is increased. For example, the precipitation power of some cations and anions varies in the following order 

Al³⁺ > Ba²⁺ > Na⁺ , Similarly [Fe(CN)₆]^-3 > SO₄^-2 > Cl^-

The precipitation power of electrolyte is determined by finding the minimum concentration (millimoles / lit) required to cause precipitation of a sol in 2hours. This value is called flocculation value. The smaller the flocculation value greater will be precipitation.

(a) ∆S decreases – ∆S is -ve

(d) both the magnitude and sign of the charge