Two statements are given below

Statements I : Adsorption of a gas on the surface of charcoal is primarily an exothermic reaction.

Statement II : A closed vessel contains $\mathrm{O}_2, \mathrm{H}_2, \mathrm{Cl}_2$, $\mathrm{NH}_3$ gases. Its pressure is $p$ (atm). About 1 g of charcoal is added to this vessel and after some time its pressure was found to be less than $p$ (atm)

The correct answer is

The critical temperature of $A, B, C, D$ gases are 190 K , $630 \mathrm{~K}, 261 \mathrm{~K}, 400 \mathrm{~K}$ respectively. The quantity of gas adsorbed per gram of charcoal at same pressure is least for the gas

' $A$ ' is a protecting colloid. The following data is obtained for preventing the coagulation of 10 mL of gold sol to which 1 mL of $10 \% \mathrm{NaCl}$ is added. What is the gold number of ' $A$ '?

Expt. No.	Wt (in mg ) of $\boldsymbol{A}$ added to gold sol	$$ \text { Coagulation } $$
1	40	Prevented
2	35	Prevented
3	25	Not prevented
4	32	Not prevented
5	33	Prevented

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

Conc. of $\mathrm{Cl}^{-}$in $\mathrm{mol} \mathrm{L}^{-1}$	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?