Which one has the highest coagulation power?

Label the hydrophilic and hydrophobic parts in the following compounds.
$(i)$ $CH_3(CH_2)_{10}CH_2OSO_3^-Na^{+}$
$(ii)$ $CH_3(CH_2)_{15}N^{+}(CH_3)_3Br^{-}$
$(iii)$ $CH_3(CH_2)_{16}COO(CH_2CH_2O)_nCH_2CH_2OH$

Give an example of a solid sol in which the dispersed phase is solid.

On adding a few drops of dilute $HCl$ or $FeCl_3$ to freshly precipitated ferric hydroxide,a red-coloured colloidal solution is obtained. This phenomenon is known as:

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

$20 \ mL$ of $0.5 \ M \ NaCl$ is required to coagulate $200 \ mL$ of $As_2S_3$ sol in $2$ hours. The coagulating value of $NaCl$ is $...........$.