Which of the following ions has greater coagulating power for a negatively charged sol?

The simplest way to check whether a system is colloidal,is

Coagulating value of electrolytes $AlCl_3$ and $NaCl$ for $As_2S_3$ are $0.09$ and $50.04$ respectively. The coagulating power of $AlCl_3$ is $x$ times the coagulating power of $NaCl$. The value of $x$ is $.......$.

At the critical micelle concentration,the surfactant molecules

The following data is obtained for coagulating a positively charged sol in $2$ hours:

Conc. of $Cl^{-}$ in $mol \cdot L^{-1}$	Result
$5 \times 10^{-5}$	Sol not precipitated
$6 \times 10^{-5}$	Sol not precipitated
$7 \times 10^{-5}$	Sol precipitated
$8 \times 10^{-5}$	Sol precipitated
$1 \times 10^{-4}$	Sol precipitated

What is the coagulating value of electrolyte for this sol?

The Brownian movement exhibited by colloidal particles is a ....... property.