Luminosity observed as a result of scattering of light by particles is observed in

How many of the following statements are correct $:$
$(i)$ When freshly prepared precipitate are converted into colloidal solution then process is called peptization.
$(ii)$ Lyophilic sol are mostly of inorganic nature.
$(iii)$ Lyophilic sol are highly solvated as particles have great affinity for solvent.
$(iv)$ Lyophobic sols are reversible sols so special methods are required to prepare them.

$A$ $42.12 \% (w/v)$ solution of $NaCl$ causes precipitation of a certain sol in $10 \, hours$. The coagulating value of $NaCl$ for the sol is $.....$
[Given : Molar mass : $Na = 23.0 \, g \, mol^{-1} ; Cl = 35.5 \, g \, mol^{-1}]$

When the dispersion medium in a colloidal system is a gas,it is called ....

$A$ liquid that scatters a beam of light but leaves no residue when passed through filter paper is known as:

$Statement-1$: Micelles are formed by surfactant molecules above the critical micellar concentration $(CMC)$.
$Statement-2$: The conductivity of a solution having surfactant molecules decreases sharply at the $CMC$.