The purple of Cassius is due to the presence of $......$.

What is formed when a lyophilic sol is added to an emulsion?

Silver iodide is used for producing artificial rain because $AgI$

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

Which one of the following impurities present in a colloidal solution cannot be removed by electrodialysis?

The isoelectric point is the $pH$ at which: