Surface Chemistry · Chemistry · AP EAPCET

Choose the incorrect statement from the following.

Which of the following statements regarding adsorption theory of heterogeneous catalysis is not correct ?

Match the following

The critical micelle concentration (CMC) of a soap solution is $5 \times 10^{-4} \mathrm{~mol} \mathrm{~L}^{-1}$. Identify the correct statements about this solution.

I. The micelle is stable if the soap solution concentration is $10^{-7} \mathrm{~mol} \mathrm{~L}^{-1}$.

II. The micelle is stable if the soap solution concentration is higher than $5 \times 10^{-4} \mathrm{~mol} \mathrm{~L}^{-1}$.

III. Micelles are also known as associated colloids.

$$ \text { Match the following } $$

$$ \begin{array}{llll} \hline & \begin{array}{l} \text { List-I } \\ \text { (Sol) } \end{array} & & \begin{array}{c} \text { List-II } \\ \text { (Method of preparation) } \end{array} \\ \hline \text { (A) } & \mathrm{As}_2 \mathrm{~S}_3 & \text { I. } & \text { Bredig's arc method } \\ \hline \text { (B) } & \mathrm{Au} & \text { II. } & \text { Oxidation } \\ \hline \text { (C) } & \mathrm{S} & \text { III. } & \text { Hydrolysis } \\ \hline \text { (D) } & \mathrm{Fe}(\mathrm{OH})_3 & \text { IV. } & \text { Double decomposition } \\ \hline \end{array} $$

The correct answer is

Observe the following reactions

I. $\mathrm{N}_2(g)+3 \mathrm{H}_2(g) \xrightarrow[773 \mathrm{~K}, 200 \mathrm{~atm}]{x} 2 \mathrm{NH}_3(g)$

II. $\mathrm{CO}(\mathrm{g})+\mathrm{H}_2 \mathrm{O}(\mathrm{g}) \xrightarrow[673 \mathrm{~K}]{Y} \mathrm{CO}_2(\mathrm{~g})+\mathrm{H}_2(\mathrm{~g})$

III. $\mathrm{CH}_4(g)+\mathrm{H}_2 \mathrm{O}(g) \xrightarrow[1270 \mathrm{~K}]{\mathrm{z}} \mathrm{CO}(g)+3 \mathrm{H}_2(g)$

Catalysts $X, Y, Z$ respectively are

What is the indicator used in argentometric titrations?

In a Freundlich adsorption isotherm, if the slope is unity and $k$ is 0.1 , the extent of adsorption at 2 atm is ( $\log 2=0.30$ )

$$ \text { Match the following } $$

The correct answer

Adsorption of a gas on solids follows Freundlich adsorption isotherm. The graph drawn between $\log \frac{x}{m}$ (on $y$-axis) and $\log p$ (on $x$-axis) is a straight line with slope equal to 3 and intercept equal to 0.30 . What is the value of $\frac{x}{m}$ at a pressure of 2 atm ?

(Given: $\log 2=0.3$ )

In a colloidal solution, both the dispersed phase and dispersion medium are in liquid phase. What is the type of colloid?

The equation which represents Freundlich adsorption isotherm is ( $x=$ amount of gas, $m=$ mass of solid)

Which one of the following is not the correct characteristic property of physical adsorption?

In each of four separate beakers (I, II, III, IV), $X \mathrm{~mL}$ of $y \mathrm{M} \mathrm{Fe}_2 \mathrm{O}_3 x \mathrm{H}_2 \mathrm{O}$ colloidal solution is present. Equal volume and equal concentration of KCl , $\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right], \mathrm{K}_3 \mathrm{PO}_4$ and $\mathrm{K}_2 \mathrm{SO}_4$ was added into I, II, III and IV respectively.

The efficiency of precipitations in these beakers follows the order

$$ \text { Match the following } $$

$$ \begin{array}{clll} \hline & \text { List-I (Compound) } & & \text { List-II (Use) } \\ \hline \text { (A) } & \text { Kieselghur } & \text { (I) } & \text { Chromatographic material } \\ \hline \text { (B) } & \text { Silica gel } & \text { (II) } & \text { Softening of hard Water } \\ \hline \text { (C) } & \text { ZSM-5 } & \text { (III) } & \text { Filtration plants } \\ \hline \text { (D) } & \text { Hydrated zeolites } & \text { (IV) } & \begin{array}{l} \text { To convert alcohol directly } \\ \text { into gasoline } \end{array} \\ \hline \end{array} $$

The correct answer is

Identify the catalytic reaction in which both reactants are in different phases.

Consider the following.

Statement-I : Gold sol is prepared by Bredig's arc method.

Statement-II : Bredig's arc method involves only dispersion but not condensation.

The correct answer is

Identify the correct statement from the following

I. Sulphur sol is an example for multi molecular colloid.

II. Starch sol is an example for associated colloid.

III. Artificial rubber is an example for macromolecular colloid.

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

' $A$ ' 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 ' $A$ '?

$$ \text { Match List - I, with List-II. } $$

$$ \begin{array}{llll} \hline & \text { List I } & & \text { List II } \\ \hline \text { I } & \text { Colloidal antimony } & \text { A } & \text { Kalaazar } \\ \hline \text { II } & \text { Silver sol } & \text { B } & \text { Intermuscular injection } \\ \hline \text { III } & \text { Milk of magnesia } & \text { C } & \text { Eye lotion } \\ \hline \text { IV } & \text { Gold sol } & \text { D } & \text { Stomach disorder } \\ \hline \end{array} $$

' $X$ ' 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 ' $X$ '?

$$ \begin{array}{ccl} \hline \text { Expt No. } & \begin{array}{c} \text { Weight of } X \text { (in mg) } \\ \text { added to gold sol } \end{array} & \text { Coagulation } \\ \hline 1 & 24 & \text { Not prevented } \\ \hline 2 & 23 & \text { Not prevented } \\ \hline 3 & 26 & \text { Prevented } \\ \hline 4 & 27 & \text { Prevented } \\ \hline 5 & 25 & \text { Prevented } \\ \hline \end{array} $$

Given below are two statements.

Statements I Easily liqueflable gases are readily adsorbed.

Statements II Adsorption enthalpy for physisorption is less compared to adsorption enthalpy for chemisorption.

The correct answer is

The correct order of coagulating power of the following ions to coagulate the positive sol is

$$\mathrm{\mathop {{{[Fe{{(CN)}_6}]}^{4 - }}}\limits_I ,\mathop {C{l^ - }}\limits_{II} ,\mathop {SO_4^{2 - }}\limits_{III}}$$

The macromolecular colloids of the following are

I. Starch solution

II. Sulphur sol

III. Synthetic detergent

IV. Synthetic rubber

Assertion (A) Animal skins are colloidal in nature.

Reason (R) Animal skin has positively charged particles.

The diameters range of colloidal particles is approximately.

Which statements among the following are correct?

1. Freundlich isotherm fails at high pressure of the gas.

2. $$\Delta H < 0$$ for both physical and chemical adsorption.

3. Physical adsorption in non-selective.

4. Chemical adsorption is reversible, whereas physical adsorption is irreversible.

In an adsorption experiment, a graph between $$\log (x / m)$$ versus $$\log p$$ was found to be linear with a slope of $$45^{\circ}$$. The intercept on $$\log (x / m)$$ axis was found to be 0.3010. The amount of gas adsorbed per gram of charcoal under a pressure of $$0.5 \mathrm{~atm}$$ is

Among the following, in which type of chromatography, both stationary and mobile phases are in liquid state?

The protective power of a lyophilic colloidal sol is expressed in terms of

A plot of $$\log (x / m)$$ versus $$\log (p)$$ for adsorption of a gas on a solid gives a straight line with a slope of