Description : Which of the following is incorrect about heterogeneous catalysis? a. The most effective catalysts are those which have small surface area b. Seperation of catlyst is easy c. Increase in the rate of reaction is due to decrease in the activation energy d. It is based upon the phenomenon of adsorption
Last Answer : a. The most effective catalysts are those which have small surface area
Description : Adsorption is the phenomenon in which a substance :
Last Answer : Adsorption is the phenomenon in which a substance : A. accumulates on the surface of the other ... close to the other substance D. None of these
Description : Chemisorption (chemical adsorption) is (A) Same as "Van der Waals" adsorption (B) Characterised by adsorption of heat (C) An irreversible phenomenon (D) A reversible phenomenon
Last Answer : (C) An irreversible phenomenon
Description : Though, theoretically the adsorption & desorption isotherms is expected to coincide but sometimes at least a part of the isotherms does not coincide and this phenomenon is known as adsorption hysteresis. In such ... (B) Higher than (C) Same as (D) Either same or higher than
Last Answer : (A) Lower than
Description : Assertion(A): Physical adsorption of molecules on the surface requires activation energy. Reason(R): Because the bonds of adsorbed molecules are broke
Last Answer : Assertion(A): Physical adsorption of molecules on the surface requires activation energy. Reason(R): ... D. If both Assertion & Reason are False.
Description : Adsorption of a gas on a surface follows Freundlich adsorption isotherm. Plot of `"log " (x)/(m)` versus log P gives a straight line with slope equal
Last Answer : Adsorption of a gas on a surface follows Freundlich adsorption isotherm. Plot of `"log " (x ... of pressure. D. Adsorption is independent of pressure.
Description : The following statement relate to the adsorption of gases on a solid surface. Identify the incorrect statement among them :
Last Answer : The following statement relate to the adsorption of gases on a solid surface. Identify the ... are increased D. Entropy of adsorption is negative
Description : The correct statement(s) pertiaining to the adsorption of a gas on a solid surface is (are)
Last Answer : The correct statement(s) pertiaining to the adsorption of a gas on a solid surface is (are) A. ... it is very slow due to higher energy of activation.
Description : In case of physical adsorption, the difference between heat of adsorption and heat of normal condensation is (A) Equal to the heat of formation of surface compound (B) Equal to the heat of wetting (C) Zero (D) Called integral heat of adsorption
Last Answer : (B) Equal to the heat of wetting
Description : Which of the following is not a chemical step in a fluid solid catalytic reaction? (A) Surface chemical reaction (B) Adsorption (C) Desorption (D) None of these
Last Answer : (D) None of these
Description : In Langmuir treatment of adsorption, (A) Whole surface of the catalyst does not have the same activity for adsorption and there is attraction between the adsorbed molecule (B) Whole surface of ... same mechanism (D) Extent of adsorption is more than one complete monomolecular layer on the surface
Last Answer : (B) Whole surface of the catalyst is essentially uniform and the adsorbed molecule has no effect on the rate of adsorption per site
Description : The rate expression for a heterogeneous catalytic reaction is given by, - rA = K.KA PA(1 + KA.PA + KR.PR), where K is surface reaction rate constant and KA and KR are absorption equilibrium constants of A and R respectively. If KR PR ... R and A) (A) E (B) E + ΔHA (C) E + ΔHA - ΔHR ) (D) ΔHA + ΔHR
Last Answer : (C) E + ΔHA - ΔHR )
Description : Brunauer, Emmet and Teller (BET) equation is used to determine the specific surface area of a porous particle but not the pore volume & the porosity of the catalyst bed. Which of the following postulates ... (except the first one) is involved in each of the evaporation process (D) None of these
Last Answer : (B) There is no dynamic equilibrium between successive layer
Description : Explain two applications of adsorption.
Last Answer : Explain two applications of adsorption.
Description : Explain how the adsorption of gas on solid varies with : a. nature of adsorbate and adsorbent
Last Answer : Explain how the adsorption of gas on solid varies with : a. nature of adsorbate and adsorbent b. surface area of adsorbent
Description : Oil rises up the wick in a lamp because (1) Oil is very light (2) Of the diffusion of oil through the wick (3) Of the surface tension phenomenon (4) Of the capillary action phenomenon
Last Answer : (4) Of the capillary action phenomenon Explanation: It is because of the capillary action phenomenon because of which oil rise up the wick in a lamp. Capillary action, or capillarity, is the ability ... such as paper, in some nonporous materials such as liquefied carbon fiber, or in a cell.
Description : Light waves projected on oil surface show seven colours due to the phenomenon of (1) polarisation (2) refraction (3) reflection (4) interference
Last Answer : (4) interference Explanation: In physics, interference is a phenomenon in which two waves superpose to form a resultant wave of greater, lower, or the same amplitude.
Description : Stars in the sky appear to twinkle due to – (1) a series of refractions (2) a series of reflections (3) a surface tension phenomenon (4) multiple diminishing brightness
Last Answer : (1) a series of refractions Explanation: The movement of air (sometimes called turbulence) in the atmosphere of Earth causes a series of refractions which makes the starlight to get slightly bent as it ... directly and some gets bent slightly away. To our eyes, this makes the star seem to twinkle.
Description : The phenomenon of ejection of electrons from the metal surface when a light of suitable frequency falls on it is called
Last Answer : Photoelectric effect
Description : The following are true: a. Kirschman's law: the greatest contrast in colour is seen when the luminosity differnece is small b. Emmbert's law: the perceived size of an object varies in ... image in the periphery of the retina tends to fade or disappear during steady fixation of another objec
Last Answer : Troxler's phenomenon: an image in the periphery of the retina tends to fade or disappear during steady fixation of another objec
Description : Which of the following resistances is not involved in a gas phase catalytic (gas-solid) reaction? (A) Ash resistance (B) Gas film and pore surface diffusion resistances for reactants (C) Surface phenomenon resistance (D) Gas film and pore surface diffusion resistances for products
Last Answer : (A) Ash resistance
Description : Which one of the following statements is correct ? (a) Dynamic viscosity is the property of a fluid which is not in motion (b) Surface energy is a fluid property giving rise to the phenomenon ... results from the action of very high pressure (d) Real fluids have lower viscosity than ideal fluids
Last Answer : (d) Real fluids have lower viscosity than ideal fluids
Description : The phenomenon of Newton’s rings can be used to check the __________. A. Wavelength of monochromatic light B. phase coherence of two sources C. flatness of any glass surface D. velocity of light
Last Answer : A. Wavelength of monochromatic light
Description : What is the name of the phenomenon that causes an accumulation of heat in the lower atmosphere because of the absorption of longwave radiation from the Earth's surface?
Last Answer : ANSWER: GREENHOUSE EFFECT
Description : Stars in the sky appear to twinkle due to (1) a series of refractions (2) a series of reflections (3) a surface tension phenomenon (4) multiple diminishing brightness
Last Answer : a series of refractions
Last Answer : Of the capillary action phenomenon
Description : Assertion :- The graphical representation of physical adsorption with temp is Reason :- This is weak adsorption & adsorption is exothermic process.
Last Answer : Assertion :- The graphical representation of physical adsorption with temp is Reason :- This is weak ... D. If both Assertion & Reason are False.
Description : In frenudlich adsorption isotherm, the value of `1//n` is
Last Answer : In frenudlich adsorption isotherm, the value of `1//n` is A. 1 in case of physical adsorption B. 1 in ... in all case D. between 2 and 4 in all cases
Description : If `x` is the amount of adsorbate and `m` is the amount of adsorbent, which of the following relation is related to adsorption process?
Last Answer : If `x` is the amount of adsorbate and `m` is the amount of adsorbent, which of the following relation is related to ... (x/m) D. `(x)/(m)= p xx T`
Description : The Langmuir adsorption isotherm is deduced using the assumption.
Last Answer : The Langmuir adsorption isotherm is deduced using the assumption. A. The adsorption isotherm is ... D. The adsorption takes place in multilayers.
Description : Assertion :- A sol of `As_(2)S_(3)` prepared by the action of `H_(2)S` on `As_(2)O_(3)` is negatively charge. Reason :- Due to adsorption of `S^(-2)`
Last Answer : Assertion :- A sol of `As_(2)S_(3)` prepared by the action of `H_(2)S` on `As_(2)O_(3) ... Reason is False. D. If both Assertion & Reason are False.
Description : According to Freundlich adsorption isotherm, which of the following is correct ?
Last Answer : According to Freundlich adsorption isotherm, which of the following is correct ? A. `(x)/(m ... the above are correct for different ranges of pressure
Description : The ease of adsorption of the hydrated alkali metal ions on ion-exchange resins follows the order:
Last Answer : The ease of adsorption of the hydrated alkali metal ions on ion-exchange resins follows the order: A. `K^(+)lt Na + ... (+)lt K^(+)lt Na^(+)lt Li^(+)`
Description : Frendlich adsorption isotherms are properly represented as in
Last Answer : Frendlich adsorption isotherms are properly represented as in A. B. C. D.
Description : An adsorption isotherm equation proposed by Langmuir is of the form `V = (V_(0)bPO)/((1 + bP))` where V is the volume of gas adsorbed at pressure P. F
Last Answer : An adsorption isotherm equation proposed by Langmuir is of the form `V = (V_(0)bPO)/((1 + bP))` where V is ... of V on P can be depicted as B. C. D.
Description : 100 mL of 0.3 M acetic acid is shaken with 0.8 g wood charcoal. The final concentration of acetic acid in the solution after adsorption is 0.125 M. Th
Last Answer : 100 mL of 0.3 M acetic acid is shaken with 0.8 g wood charcoal. The final concentration of acetic acid in the ... g` C. `1.31 g` D. `0.131 g`
Description : Adsorption of a gas follows Freundlich adsorption isotherm. In the given plot, x is the mass of the gas adsorbed on mass m of the adsorbent at pressur
Last Answer : Adsorption of a gas follows Freundlich adsorption isotherm. In the given plot, x is the mass of the gas adsorbed on mass m ... p^(1//2)` D. `p^(1//4)`
Description : Which one of the following is not a property of physical adsorption ?
Last Answer : Which one of the following is not a property of physical adsorption ? A. Higher the ... , more the adsorption D. Unilayer adsorption occurs
Description : Two compounds I and II are eluted by column chromatography (adsorption of `I gt II`). Which one of the following is a correct statement ?
Last Answer : Two compounds I and II are eluted by column chromatography (adsorption of `I gt II`). Which one of the ... slower and has higher `R_(f)` value than I
Description : A particular adsorption process has the following characteristics : (i) It arises due to vander Waals forces and (ii) it is reversible. Identify the c
Last Answer : A particular adsorption process has the following characteristics : (i) It arises due to vander Waals ... temperature. D. Energy of activation is low.
Description : For a linear plot of log(x/m) versus log p in a Freundlich adsorption isotherm, which of the following statements is correct ? (k and n are constants)
Last Answer : For a linear plot of log(x/m) versus log p in a Freundlich adsorption isotherm, which of the following ... Both k and 1/n appear in the slope term.
Description : According to Freundlich adsorption isotherm, which of the following is correct?
Last Answer : According to Freundlich adsorption isotherm, which of the following is correct? A. `(x)/(m) ... the above are correct for different ranges of pressure
Description : Which one of the following characteristics is not correct for physical adsorption ?
Last Answer : Which one of the following characteristics is not correct for physical adsorption ? A. ... enthalpy and entropy of adsorption are negative.
Description : Which of the following statements regarding adsorption is/are correct?
Last Answer : Which of the following statements regarding adsorption is/are correct? A. Extent of adsorption ... adsorption is dependent on the nature of adsorbent
Description : Which of the following statements about physical adsorption is correct ?
Last Answer : Which of the following statements about physical adsorption is correct ? A. It is always ... enthalpy of adsorption as compared to chemisorption.
Description : Identify the appropriate graph between enthalpy and progress of physical adsorption.
Last Answer : Identify the appropriate graph between enthalpy and progress of physical adsorption. A. B. C. D.
Description : There is desorption of physical adsorption when
Last Answer : There is desorption of physical adsorption when A. temperature is increased B. temperature is ... pressure is increased D. concentration is increased
Description : Following is the variation of physical adsorption with temperature.
Last Answer : Following is the variation of physical adsorption with temperature. A. B. C. D.
Description : What is adsorption?
Last Answer : What is adsorption?