The number of statement/s which are the characteristics of physisorption is __________
A. It is highly specific in nature
B. Enthalpy of adsorption is high
C. It decreases with increase in temperature
D. It results into unimolecular layer
E. No activation energy is needed
A. It is highly specific in nature
B. Enthalpy of adsorption is high
C. It decreases with increase in temperature
D. It results into unimolecular layer
E. No activation energy is needed
Show Hint
Physisorption decreases with temperature and requires no activation energy, as it involves weak van der Waals forces.
Correct Answer: 2
Solution and Explanation
• Physisorption:
– It decreases with an increase in temperature because it is an exothermic process (Statement C is correct).
– It requires no significant activation energy (Statement E is correct).
• Statements A, B, and D describe chemisorption and are incorrect for physisorption.
Thus, 2 statements (C and E) are correct.
Top Questions on Adsorption
- 500 mg of a dry adsorbent is added to a beaker containing 100 mL solution of concentration 100 mg phenol/(L solution). The adsorbent is separated out after 5 h of rigorous mixing. If the residual concentration in the solution after separating the adsorbent is 30 mg phenol/(L solution), the amount of phenol adsorbed (in mg per gram of dry adsorbent) is:
- GATE CH - 2025
- Heat Transfer
- Adsorption
- Which term from the following is not related to adsorption?
- CUET (UG) - 2024
- Chemistry
- Adsorption
- Which of the following can adsorb larger volume of hydrogen gas?
- Kirkbride equation is used for determining the —————.
- Which of the following happens in the use of Raschig rings in place of crushed stones as packing in packed beds (other things being same)?
Questions Asked in JEE Main exam
- Let \( y = f(x) \) be the solution of the differential equation\[\frac{dy}{dx} + \frac{xy}{x^2 - 1} = \frac{x^6 + 4x}{\sqrt{1 - x^2}}, \quad -1 < x < 1\] such that \( f(0) = 0 \). If \[6 \int_{-1/2}^{1/2} f(x)dx = 2\pi - \alpha\] then \( \alpha^2 \) is equal to __________.
- JEE Main - 2025
- Differential equations
- Marks obtained by all the students of class 12 are presented in a frequency distribution with classes of equal width. Let the median of this grouped data be 14 with median class interval 12-18 and median class frequency 12. If the number of students whose marks are less than 12 is 18, then the total number of students is:
- JEE Main - 2025
- Statistics
- Let the system of equations $ x + 5y - z = 1 $ $ 4x + 3y - 3z = 7 $ $ 24x + y + \lambda z = \mu $ where $ \lambda, \mu \in \mathbb{R} $, have infinitely many solutions. Then the number of the solutions of this system, if $x, y, z$ are integers and satisfy $7 \leq x + y + z \leq 77$, is:
- JEE Main - 2025
- Linear Systems and Determinants
- A force of 49 N acts tangentially at the highest point of a sphere (solid of mass 20 kg) kept on a rough horizontal plane. If the sphere rolls without slipping, then the acceleration of the center of the sphere is:
- JEE Main - 2025
- Quantum Mechanics
Match List-I with List-II: List-I
- JEE Main - 2025
- Classification Of Organic Compounds
Concepts Used:
Surface Chemistry
The study of the chemical phenomena that occur at the interface of two surfaces which can be solid-liquid, solid-gas, solid-vacuum, liquid-gas, etc.
Read Also: Surface Chemistry
Applications of surface chemistry are:
Adsorption:
The process of attraction and aggregation of the molecules of a substance on the surface of a solid is known as adsorption. For Example, N2 adsorbs on the surface of activated charcoal
Two types of adsorption are:-
- Chemisorption: It is also known as Chemical Adsorption.
- Physisorption: It is also known as Physical Adsorption.
Corrosion:
The process through which the refined metals convert themselves into more stable compounds is known as corrosion.
Crystallisation:
The type of technique used in order to purify the substances to separate Solids from liquids is known as crystallisation.
Heterogeneous Catalysis:
The process wherein a catalyst is used in order to increase the rate of a chemical reaction is known as catalysis. The catalyst does not undergo any transformation and can be recovered in a chemically unchanged state.
There are two types of catalysis:-
- When the catalyst involved and the reacting substances are same states of matter or in the same phase, it is known as Homogeneous Catalysis.
- When the catalyst involved and the reacting substances are in different states of matter or different phases, it is known as Heterogeneous Catalysis.