Q: Which of the following nanomaterials has one dimension < 100 nm?

Nanomaterials are classified based on the number of dimensions that lie in the nanoscale range (1 to 100 nm). Zero-dimensional (0D) nanomaterials have all three dimensions in the nanoscale. Examples include quantum dots and nanoparticles. One-dimensional (1D) nanomaterials have two dimensions in the nanoscale. Examples include nanowires and nanotubes. Two-dimensional (2D) nanomaterials have exactly one dimension in the nanoscale. Examples include thin films, graphene, and nanosheets. Three-dimen

Q: Identify the term used to describe movement of colloidal particles under applied electric potential without using semipermeable membrane.

The movement of colloidal particles under the influence of an applied electric potential is called electrophoresis. When the movement of colloidal particles is prevented by some suitable means (like a semipermeable membrane), it is observed that the dispersion medium begins to move in an electric field. This phenomenon is termed electroosmosis. Since the question specifies the movement of colloidal particles without using a semipermeable membrane, the correct term is electrophoresis. Answer: Ele

Q: Which of the following ranges of particle size defines nano scale ?

Nanoscale is defined as the size range from 1 nm to 100 nm. Particles with at least one dimension in this size range are considered nanoparticles. Answer: 1 - 100 nm

Q: Which of following forces is responsible for physisorption ?

Physisorption, also known as physical adsorption, arises due to weak van der Waals forces between the adsorbate and the adsorbent. London force of dispersion is a type of van der Waals force and is the primary force responsible for physisorption. Coulombic and electrostatic forces are strong forces typically associated with ionic interactions or chemisorption, while hydrogen bonding is a specific dipole-dipole interaction not universally responsible for physisorption. Answer: London force of dis

Q: Which of the following properties of colloid is used to measure the rate of migration of sol particles?

Electrophoresis is the phenomenon of movement of colloidal particles under the influence of an applied electric field. By observing this movement, the rate of migration of sol particles can be measured. Tyndall effect is the scattering of light by colloidal particles. Brownian motion is the continuous zig-zag motion of colloidal particles. Electroosmosis is the movement of the dispersion medium under an electric field when the colloidal particles are prevented from moving.

Q: Which of the following is an example of macromolecular colloid?

Macromolecular colloids are formed when large molecules (macromolecules) having colloidal dimensions are dispersed in a suitable dispersion medium. Examples include naturally occurring macromolecules such as starch, cellulose, proteins, and enzymes, as well as man-made polymers like polythene, nylon, and polystyrene. Soaps and detergents are examples of associated colloids (micelles), which are formed by the aggregation of a large number of ions in concentrated solutions. Sulphur sol, consisting

Q: Which from following anions has greater power for coagulation of positive sol?

According to the Hardy-Schulze rule, the coagulating power of an ion is directly proportional to the magnitude of its charge (valency). For the coagulation of a positive sol, an anion is required. The given anions and their charge magnitudes are: Cl ^- : 1 SO _4^ 2- : 2 PO _4^ 3- (given as PO _4^ 2- in options) : 3 [ Fe(CN) _6]^ 4- : 4 Since [ Fe(CN) _6]^ 4- has the highest negative charge, it possesses the maximum coagulating power among the given options.

Q: Which from following is NOT an example of oil in water emulsion?

Emulsions are broadly classified into two types based on the dispersed phase and dispersion medium: 1. Oil in water (O/W) emulsion: In this type, oil acts as the dispersed phase and water acts as the dispersion medium. Examples include milk, vanishing cream, and paint. 2. Water in oil (W/O) emulsion: In this type, water acts as the dispersed phase and oil acts as the dispersion medium. Examples include butter, cold cream, and cod liver oil. Since butter is a water in oil (W/O) emulsion, it is no

Q: Identify a nanomaterial having all three dimensions less than 100 nm?

Nanomaterials are classified based on the number of dimensions that are not confined to the nanoscale range ( Zero-dimensional (0D) nanomaterials have all three dimensions in the nanoscale range (less than 100 nm). Examples include quantum dots, nanoparticles, and fullerenes. One-dimensional (1D) nanomaterials have two dimensions in the nanoscale and one macroscopic dimension. Examples include nanotubes, nanowires, and nanofibers. Two-dimensional (2D) nanomaterials have one dimension in the nano

Q: Which of the following properties is responsible for the development of colour to the colloids?

The colour of a colloidal solution depends on the wavelength of light scattered by the dispersed particles. The scattering of light by colloidal particles is known as the Tyndall effect. Therefore, the Tyndall effect is responsible for the development of colour in colloids. Answer: Tyndall effect

Question 1

Which of the following nanomaterials has one dimension < 100 nm?

Accepted Answer

Nanomaterials are classified based on the number of dimensions that lie in the nanoscale range (1 to 100 nm). Zero-dimensional (0D) nanomaterials have all three dimensions in the nanoscale. Examples include quantum dots and nanoparticles. One-dimensional (1D) nanomaterials have two dimensions in the nanoscale. Examples include nanowires and nanotubes. Two-dimensional (2D) nanomaterials have exactly one dimension in the nanoscale. Examples include thin films, graphene, and nanosheets. Three-dimen

Question 2

Identify the term used to describe movement of colloidal particles under applied electric potential without using semipermeable membrane.

Accepted Answer

The movement of colloidal particles under the influence of an applied electric potential is called electrophoresis. When the movement of colloidal particles is prevented by some suitable means (like a semipermeable membrane), it is observed that the dispersion medium begins to move in an electric field. This phenomenon is termed electroosmosis. Since the question specifies the movement of colloidal particles without using a semipermeable membrane, the correct term is electrophoresis. Answer: Ele

Question 3

Which of the following ranges of particle size defines nano scale ?

Accepted Answer

Nanoscale is defined as the size range from 1 nm to 100 nm. Particles with at least one dimension in this size range are considered nanoparticles. Answer: 1 - 100 nm

Question 4

Which of following forces is responsible for physisorption ?

Accepted Answer

Physisorption, also known as physical adsorption, arises due to weak van der Waals forces between the adsorbate and the adsorbent. London force of dispersion is a type of van der Waals force and is the primary force responsible for physisorption. Coulombic and electrostatic forces are strong forces typically associated with ionic interactions or chemisorption, while hydrogen bonding is a specific dipole-dipole interaction not universally responsible for physisorption. Answer: London force of dis

Question 5

Which of the following properties of colloid is used to measure the rate of migration of sol particles?

Accepted Answer

Electrophoresis is the phenomenon of movement of colloidal particles under the influence of an applied electric field. By observing this movement, the rate of migration of sol particles can be measured. Tyndall effect is the scattering of light by colloidal particles. Brownian motion is the continuous zig-zag motion of colloidal particles. Electroosmosis is the movement of the dispersion medium under an electric field when the colloidal particles are prevented from moving.

Question 6

Which of the following is an example of macromolecular colloid?

Accepted Answer

Macromolecular colloids are formed when large molecules (macromolecules) having colloidal dimensions are dispersed in a suitable dispersion medium. Examples include naturally occurring macromolecules such as starch, cellulose, proteins, and enzymes, as well as man-made polymers like polythene, nylon, and polystyrene. Soaps and detergents are examples of associated colloids (micelles), which are formed by the aggregation of a large number of ions in concentrated solutions. Sulphur sol, consisting

Question 7

Which from following anions has greater power for coagulation of positive sol?

Accepted Answer

According to the Hardy-Schulze rule, the coagulating power of an ion is directly proportional to the magnitude of its charge (valency). For the coagulation of a positive sol, an anion is required. The given anions and their charge magnitudes are: Cl ^- : 1 SO _4^ 2- : 2 PO _4^ 3- (given as PO _4^ 2- in options) : 3 [ Fe(CN) _6]^ 4- : 4 Since [ Fe(CN) _6]^ 4- has the highest negative charge, it possesses the maximum coagulating power among the given options.

Question 8

Which from following is NOT an example of oil in water emulsion?

Accepted Answer

Emulsions are broadly classified into two types based on the dispersed phase and dispersion medium: 1. Oil in water (O/W) emulsion: In this type, oil acts as the dispersed phase and water acts as the dispersion medium. Examples include milk, vanishing cream, and paint. 2. Water in oil (W/O) emulsion: In this type, water acts as the dispersed phase and oil acts as the dispersion medium. Examples include butter, cold cream, and cod liver oil. Since butter is a water in oil (W/O) emulsion, it is no

Question 9

Identify a nanomaterial having all three dimensions less than 100 nm?

Accepted Answer

Nanomaterials are classified based on the number of dimensions that are not confined to the nanoscale range ( Zero-dimensional (0D) nanomaterials have all three dimensions in the nanoscale range (less than 100 nm). Examples include quantum dots, nanoparticles, and fullerenes. One-dimensional (1D) nanomaterials have two dimensions in the nanoscale and one macroscopic dimension. Examples include nanotubes, nanowires, and nanofibers. Two-dimensional (2D) nanomaterials have one dimension in the nano

Question 10

Which of the following properties is responsible for the development of colour to the colloids?

Accepted Answer

The colour of a colloidal solution depends on the wavelength of light scattered by the dispersed particles. The scattering of light by colloidal particles is known as the Tyndall effect. Therefore, the Tyndall effect is responsible for the development of colour in colloids. Answer: Tyndall effect

Question 11

Nano materials not applied in

Accepted Answer

Nanomaterials are extensively used in the manufacturing of scratch-proof glasses, electronic devices, and self-cleaning materials (such as titanium dioxide nanoparticles). Conventional water treatment relies on traditional physical and chemical processes like coagulation, flocculation, sedimentation, and sand filtration, which do not involve the use of nanomaterials. Advanced water treatment may use nanomaterials, but conventional methods do not. Answer: Conventional water treatment

Question 12

Which of the following exhibits the minimum coagulating power for precipitating of positively charged ferric oxide sol ?

Accepted Answer

According to the Hardy-Schulze rule, the coagulating power of an ion is directly proportional to the magnitude of its charge. Since the ferric oxide sol is positively charged, the anions of the added electrolyte are responsible for its coagulation. The anions provided by the given electrolytes are: KNO _3 NO _3^ - (charge magnitude = 1) K _2 SO _4 SO _4^ 2- (charge magnitude = 2) K _3 PO _4 PO _4^ 3- (charge magnitude = 3) K _4[ Fe(CN) _6] [ Fe(CN) _6]^ 4- (charge magnitude = 4) The order of coa

Question 13

What is the role of catalyst in catalytic reaction ?

Accepted Answer

A catalyst increases the rate of a chemical reaction by providing an alternative reaction pathway that has a lower activation energy. It does not alter the enthalpy, entropy, or Gibbs free energy of the reaction. Thus, the primary role of a catalyst is to decrease the energy of activation of the reaction. Answer: It decreases the energy of activation of reaction.

Question 14

Which of the following is applicable to thin film?

Accepted Answer

Nanostructures are classified based on the number of dimensions that are not confined to the nanoscale range ( Zero-dimensional (0D) nanostructures have all three dimensions in the nanoscale (e.g., quantum dots, nanoparticles). One-dimensional (1D) nanostructures have two dimensions in the nanoscale and one extended dimension (e.g., nanowires, nanotubes). Two-dimensional (2D) nanostructures have one dimension in the nanoscale (thickness) and two extended dimensions (length and width). A thin fil

Question 15

Match List I with List II List I List II (A). Brownian Motion (I). Removal of impurities from the colloidal sols using a semipermeable membrane. (B). Tyndall Effect (II). Movement of colloidal particl

Accepted Answer

Brownian motion is the continuous random zig-zag movement of colloidal particles due to unequal bombardment by the molecules of the dispersion medium. Thus, (A) (III). Tyndall effect is the scattering of light by colloidal particles, making the path of light visible. Thus, (B) (IV). Electrophoresis is the movement of colloidal particles towards oppositely charged electrodes under the influence of an applied electric field. Thus, (C) (II). Dialysis is the process of removing dissolved impurities

Question 16

Which of the following nano structures includes nanotubes as an example?

Accepted Answer

Nanomaterials are classified based on the number of dimensions that are outside the nanoscale range (greater than 100 nm). Zero-dimensional (0D) nanomaterials have all three dimensions in the nanoscale. Examples include quantum dots and nanoparticles. One-dimensional (1D) nanomaterials have two dimensions in the nanoscale and one dimension outside the nanoscale. Examples include nanotubes, nanowires, and nanorods. Two-dimensional (2D) nanomaterials have one dimension in the nanoscale and two dim

Question 17

Which of the following is a water-in-oil type of emulsion?

Accepted Answer

Emulsions are colloidal systems in which both the dispersed phase and the dispersion medium are liquids. In a water-in-oil (W/O) emulsion, water is the dispersed phase and oil is the dispersion medium. Butter is an example of a water-in-oil emulsion, where water is dispersed in fat (oil). Milk and vanishing cream are examples of oil-in-water (O/W) emulsions, where oil is dispersed in water. Answer: Butter

Question 18

Identify the correct statement regarding lyophilic colloid from the following.

Accepted Answer

The word lyophilic means liquid-loving or solvent-loving. Therefore, lyophilic colloids are solvent-loving colloids. They are reversible in nature because if the dispersion medium is separated from the dispersed phase, the sol can be reconstituted by simply remixing with the dispersion medium. They can be prepared easily by directly mixing the dispersed phase with the dispersion medium, without requiring any special methods. Answer: It is solvent loving colloid.

Question 19

Which of the following statements is correct for the spontaneous adsorption of a gas?

Accepted Answer

During the adsorption of a gas, the gas molecules are restricted to the surface of the solid, which decreases their randomness or entropy. Thus, the change in entropy, S, is negative. For a process to be spontaneous, the change in Gibbs free energy, G, must be negative. According to the Gibbs-Helmholtz equation: G = H - T S Since S is negative, the term -T S becomes positive. For G to be negative, the enthalpy change, H, must be negative and its magnitude must be large enough to overcome the pos

Question 20

Identify the dimensional nature of nanoparticles by the following.

Accepted Answer

Nanomaterials are classified based on the number of dimensions that are not confined to the nanoscale range (1-100 nm). Zero-dimensional (0D) nanomaterials have all three dimensions in the nanoscale. Examples include nanoparticles, quantum dots, and fullerenes. One-dimensional (1D) nanomaterials have two dimensions in the nanoscale. Examples include nanotubes and nanowires. Two-dimensional (2D) nanomaterials have one dimension in the nanoscale. Examples include graphene and nanofilms. Since nano

Surface Chemistry — Previous Year Questions & Solutions