In emulsions,the dispersion medium and dispersed phase are

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

List-$I$	List-$II$
$A$. Negatively charged sol	$I$. $Fe_{2}O_{3} \cdot xH_{2}O$
$B$. Macromolecular colloid	$II$. $CdS$ sol
$C$. Positively charged sol	$III$. Starch
$D$. Cheese	$IV$. $A$ gel

Choose the correct answer from the options given below:

What are lyophilic and lyophobic sols? Give one example of each type. Why are hydrophobic sols easily coagulated?

Which of the following surfactants will form micelles in an aqueous solution at the lowest molar concentration under specific conditions?

The Tyndall effect is observed only when the following conditions are satisfied $:$
$1$. The diameter of the dispersed particles is much smaller than the wavelength of the light used.
$2$. The diameter of the dispersed particle is not much smaller than the wavelength of the light used.
$3$. The refractive indices of the dispersed phase and dispersion medium are almost similar in magnitude.
$4$. The refractive indices of the dispersed phase and dispersion medium differ greatly in magnitude.

The size of colloidal particles is . . .