When freshly prepared $Fe(OH)_3$ precipitate is boiled in water in the presence of a few drops of dilute $HCl$,a colloidal sol of ferric hydroxide is formed. This process is known as .......

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A)$: Dissolved substances can be removed from a colloidal solution by diffusion through a parchment paper.
Reason $(R)$: Particles in a true solution cannot pass through parchment paper but the colloidal particles can pass through the parchment paper.
In the light of the above statements,choose the correct answer from the options given below.

In a colloidal solution,the movement of colloidal particles is known as?

Jelly is a colloidal solution of

$A$ sol of $AgI$ is prepared by mixing equal volumes of $0.1 \ M \ AgNO_{3}$ and $0.2 \ M \ KI$. Which of the following statements is correct?

Which one of the following is most effective in causing the coagulation of an $As_2S_3$ sol?