The catalytic poisons decrease the activity of the catalyst because they are preferentially adsorbed on the surface of catalyst.
2.
When an excess of a very dilute aqueous solution of $$KI$$ is added to a very dilute aqueous solution of silver nitrate, the colloidal particles of silver iodide are associated with which of the following Helmholtz double layer ?
As excess of $$KI$$ has been added, $${I^ - }$$ ions are adsorbed on $$AgI$$ forming a fixed layer ( and giving it a negative charge ). It then attracts the counter ions $$\left( {{K^ + }} \right)$$ from the medium forming a second layer ( diffused layer ).
3.
Among the electrolytes $$N{a_2}S{O_4},CaC{l_2},A{l_2}{\left( {S{O_4}} \right)_3}$$ and $$N{H_4}Cl,$$ the most effective coagulating agent for $$S{b_2}{S_3}$$ sol is
$$S{b_2}{S_3}$$ is a negatively charged sol. The most effective coagulating agent will be electrolyte with highest positive charge on the cation, $$viz.,A{l_2}{\left( {S{O_4}} \right)_3}.$$ The order is $$A{l^{3 + }} > C{a^{2 + }} > N{a^ + } > NH_4^ + $$
4.
Which of the following is most powerful to coagulate the negative colloid?
A.
$$ZnS{O_4}$$
B.
$$N{a_3}P{O_4}$$
C.
$$AlC{l_3}$$
D.
$${K_4}\left[ {Fe{{\left( {CN} \right)}_6}} \right]$$
According to Hardy-Schulze rule "The amount of electrolyte required to coagulate a fixed amount of a sol depends upon the sign of charge and valency of the flocculating ion."
Thus, the coagulating power vary in the order.
$$A{l^{3 + }} > Z{n^{2 + }} > N{a^ + }$$
5.
$$100\,mL$$ of $$0.6\,M$$ acetic acid is shaken with $$2\,g$$ activated carbon. The final concentration of the solution after adsorption is $$0.5\,M.$$ What is the
amount of acetic acid adsorbed per gram of carbon?
This is an example of heterogeneous catalysis as the catalyst is present in different phase than that of the reactants.
\[4N{{H}_{3\left( g \right)}}+5{{O}_{2\left( g \right)}}\xrightarrow{P{{t}_{\left( s \right)}}}\] \[4N{{O}_{\left( g \right)}}+6{{H}_{2}}{{O}_{\left( g \right)}}\]
7.
Conditions required for increase in van der Waals' adsorption are respectively
The lyophobic sols are less stable than lyophilic sols. The lyophilic sols are thus used to protect the lyophobic sols. This property of lyophilic sols is known as protective action of lyophilic sols which is represented by gold number.
9.
A plot of $${\text{log}}\left( {\frac{x}{m}} \right)$$ against log $$P$$ for the adsorption of a gas on a solid gives a straight line with slope equal to :
According to Langmuir's Model of adsorption of a gas on a solid surface the mass of gas adsorbed $$(x)$$ per gram of the adsorbent $$(m)$$ is directly proportional to the pressure of the gas $$(p)$$ at constant temperature i.e.
$$\frac{{\text{x}}}{{\text{m}}} \propto {\text{p}}$$