In the measurement of gold number,the useful electrolyte is

Flocculation value of $BaCl_2$ is much less than that of $KCl$ for sol $A$ and flocculation value of $Na_2SO_4$ is much less than that of $NaBr$ for sol $B.$ The correct statement among the following is

Which one of the following is a lyophilic colloid?

In general,for soaps,the concentration of surfactant at $CMC$ is around $mol \ L^{-1}$.

Micelles are $....$.

$A$ sample of red ink (a colloidal solution) is prepared by mixing eosin dye,egg white,$HCHO$ and water. The component which ensures stability of the ink sample is :-