List of top Chemistry Questions on Surface Chemistry

Observe the following statements: I. Micelles have both lyophilic and lyophobic parts II. Starch in water is an example for multimolecular colloid III. The CMC of a soap is \(10^{-3}\,\text{mol L}^{-1}\). It can form a micelle when its concentration is less than \(10^{-3}\,\text{mol L}^{-1}\) IV. Gold sol can be prepared by Bredig's Arc method Choose the correct statements.
The correct statements about paper chromatography are
• [I.] It is type of adsorption chromatography
• [II.] It is type of partition chromatography
• [III.] Both stationary and mobile phases are liquids
• [IV.] Stationary phase is solid and mobile phase is liquid The correct answer is
At T(K), adsorption of a gas on 1 g of solid adsorbent follows Freundlich adsorption isotherm and is represented by the given graph. What is the value of \(k\)?
Gold number of a protective colloid A is x. A mixture is prepared by adding 50 mL of 10% NaCl solution to 500 mL gold sol. What minimum mass of A is needed to prevent coagulation?
Match List-I with List-II.
At a given temperature, \(0.45\,\text{g}\) of acetic acid in \(50\,\text{mL}\) of water is shaken with \(1.0\,\text{g}\) of charcoal and the pH of the resulting solution is \(3.0\). Assume, the adsorption of acetic acid from the aqueous solution by charcoal follows Freundlich isotherm,

\[ \frac{x}{m} = kC^{1/n} \]
If the plot of \(\log_{10}(x/m)\) against \(\log_{10} C\) gives a straight line with slope \(1\), the value of \(k\) in \(\text{L mol}^{-1}\) is _______.

Given: The molar mass of acetic acid is \(60\,\text{g mol}^{-1}\).
The acid dissociation constant of acetic acid is \(1.0 \times 10^{-5}\) at the given temperature.
\(x\) is the mass (in grams) of acetic acid adsorbed.
\(m\) is the mass (in grams) of charcoal.
\(C\) is the equilibrium concentration of acetic acid in the solution after the adsorption is complete.
\(k\) and \(n\) are constants for acetic acid–charcoal system at the given temperature.
The process of adsorption is always
Which of the following is an example of physisorption?
The half-life of $^{65}$Zn is 245 days. After $x$ days, 75% of the original activity remained. The value of $x$ in days is __________ (Nearest integer).}
(Given: $\log 3 = 0.4771$ and $\log 2 = 0.3010$)
Langmuir isotherm
Water drops are spherical in shape because of:
Observe the following colloids:
I. Gold
II. Detergent
III. Starch
IV. Soap
V. Synthetic rubber
VI. Sulphur
VII. Cellulose
The number of multimolecular colloids and macromolecular colloids in the above list is respectively
Identify the correct statements from the following
I. Adsorption is an endothermic process.
II. Adsorption of a gas on the surface of a solid is accompanied by a decrease in enthalpy and a decrease in entropy.
III. Adsorption capacity of A, B and C gases on 1g of activated charcoal follows the order A>B>C. Their critical temperatures (T$_c$) follow the order T$_c$(A)>T$_c$(B)>T$_c$(C).
Freundlich adsorption isotherm: log(mx) vs log(p) increases then flattens (points C-D). Experimental condition represented by C-D?
Which from following pairs of carbohydrates produce equal quantity of glucose on hydrolysis per mole?
Which of the following is NOT a characteristic of chemisorption?
Which of the following is NOT a characteristic of chemisorption?
Which from following pairs of carbohydrates produce equal quantity of glucose on hydrolysis per mole?
Which of the following is NOT a characteristic of chemisorption?
The potential of a large liquid drop when eight liquid drops are combined is 20 V. What is the potential of each single drop?
Which of the following statement is incorrect about the nature of chemisorption?
The coagulating power of electrolytes having ions Na$^+$, Al$^{3+}$ and Ba$^{2+}$ for As$_2$S$_3$ sol increases in the order
The role of a catalyst is to change _____________ .
What is the polymer of elastomer?
TLC
In the given TLC, the distance of spot \( A \) and \( B \) are 5 cm and 7 cm, from the bottom of the TLC plate, respectively. The \( R_f \) value of \( B \) is \( x \times 10^{-1} \) times more than \( A \). The value of \( x \) is _________ .