The Tyndall effect would be observed in a

$A$ liquid aerosol is a colloidal system of

Match the following types of colloidal systems in List-$I$ with their corresponding names in List-$II$.

List-$I$	List-$II$
$(A)$ Solid dispersed in liquid	$(I)$ Emulsion
$(B)$ Liquid dispersed in liquid	$(II)$ Foam
$(C)$ Gas dispersed in liquid	$(III)$ Gel
$(D)$ Liquid dispersed in solid	$(IV)$ Sol
	$(V)$ Aerosol

The coagulation of $100 \, mL$ of a colloidal sol of gold is completely prevented by the addition of $0.25 \, g$ of a substance '$X$' to it before adding $10 \, mL$ of $1 \% \ NaCl$ solution. The gold number of '$X$' is:

$A$ peptising agent is

$A$ sol of $AgI$ is prepared by mixing equal volumes of $0.1 \ M \ AgNO_{3}$ and $0.2 \ M \ KI$. Which of the following statements is correct?