When the dispersion medium in a colloidal system is a gas,it is called ....

Which of the following is an emulsifier?

The correct statements with respect to dialysis of colloidal solution are
$I$. Colloidal particles can pass through the membrane.
$II$. Animal bladder can be used as membrane.
$III$. Cellophane is not used as membrane.
$IV$. Ions or small molecules can diffuse through membrane into water.

When silver nitrate solution is added to potassium iodide solution,then the sol produced is:

$A$ system of cellulose dispersed in alcohol is known as a ...... .

Gold numbers of protective colloids $A, B, C$ and $D$ are $0.50, 0.01, 0.10$ and $0.005$,respectively. The correct order of their protective powers is