If the molecular weight of a compound is increased,then the sensitivity is decreased in which of the following methods?

Colloidal solutions can be purified by

On addition of $1 \ mL$ of $10 \%$ $NaCl$ to $10 \ mL$ gold sol in the presence of $0.038 \ g$ of starch the coagulation is just prevented. Then the value of gold number of starch is

Hair cream is an example of which of the following?

Match List-$I$ with List-$II$.

List-$I$ (Colloid Preparation Method)	List-$II$ (Chemical Reaction)
$(a)$ Hydrolysis	$(i) \; 2 AuCl_{3} + 3 HCHO + 3 H_{2}O \rightarrow 2 Au(sol) + 3 HCOOH + 6 HCl$
$(b)$ Reduction	$(ii) \; As_{2}O_{3} + 3 H_{2}S \rightarrow As_{2}S_{3}(sol) + 3 H_{2}O$
$(c)$ Oxidation	$(iii) \; SO_{2} + 2 H_{2}S \rightarrow 3 S(sol) + 2 H_{2}O$
$(d)$ Double Decomposition	$(iv) \; FeCl_{3} + 3 H_{2}O \rightarrow Fe(OH)_{3}(sol) + 3 HCl$

Choose the most appropriate answer from the options given below.

The gold numbers of protective colloids $A, B, C$,and $D$ are $0.04, 0.004, 10$,and $40$ respectively. The order of their protective power is: