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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 451. |
Some type of gels like gelatin loose water slowly. The process is known as :A. SynerisisB. ThixotropyC. PeptisationD. Imbibition |
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Answer» Correct Answer - A Loss of water from gel is known as synerisis. |
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| 452. |
Which of the following is a mismatch?A. Lyophilic colloids-reversible solsB. Associated colloids-micellesC. Tyndall effect-scattering of light by colloidal particleD. Electrophoresis-movement of dispersion medium under the influence of electric field |
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Answer» Correct Answer - D |
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| 453. |
The correct statement (s) about surface properties is (are)A. the critical temperatures of ethane and nitrogen are 563 K and 126 K, respectively. The adsorption of ethane will be more than that of nitrogen of same amount of activated charcoal ar a given temperatureB. cloud is an emulsion type of colloid in which liquid is dispersed phase and gas is dispersion mediumC. Adsorption is accompanied by decrease in enthalpy and decrease in entropy of the systemD. Brownian motion of colloidal particles does not depend on the size of the particles but depends on viscosity of the solution |
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Answer» Correct Answer - B::C |
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| 454. |
Select correct statement (s) :A. Hydrophilic colloid is a colloid in which there is a strong attraction between the dispersed phase and waterB. hydrophobic colloid is a colloid in which there is a lack of attraction between the dispersed phase and waterC. hydrophobic sols are often formed when a solid crystallises rapidly from a chemical reaction or a supersaturated solutionD. all of the above |
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Answer» Correct Answer - D All are facts to remember. |
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| 455. |
The stabilisation of a lyophobic colloid is due to :A. preferential adsorption of similar charged particle on colloids surface.B. interaction between dispersed phase and dispersion mediumC. the formation of a covalent bond between two phases.D. the viscosity of the medium. |
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Answer» Correct Answer - A Similar charged colloidal particles will repel each other so colloidal system will not be suspended. |
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| 456. |
A reddish brown sol (containing `Fe^(3+)`) is obtained by :A. the addition of small amount of `FeCl_(3)` solution to freshly prepared `Fe(OH)_(3)` precipitateB. the addition of `Fe(OH)_(3)` to freshly prepared `FeCl_(3)` solutionC. the addition of `NH_(4)OH` to `FeCl_(3)` solution dropwiseD. the addition of NaOH to `FeCl_(3)` solution dropwise |
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Answer» Correct Answer - A |
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| 457. |
A reddish brown sol (containing `Fe^(3+)`) is obtained by :A. the addition of small amount of `FeCl_(3)` solution to freshly prepared `Fe(OH)_(3)` precipitateB. the addition of `Fe(OH)_(3)` to freshly prepared `FeCl_(3)` solutionC. the addition of `NH_(4)OH` to `FeCl_(3)` solution dropwiseD. the addition of `NaOH` to `FeCl_(3)` solution dropwise |
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Answer» Correct Answer - A Reddish brown sol is prepared by adding `FeCl_(3)` in `Fe(OH)_(3)` precipitate. |
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| 458. |
In context with the industrial preparation of hydrogen from water gas `(CO+H_(2))` , which of the following is the correct statement ?A. CO is removed by absorption in aqueous `Cu_(2)Cl_(2)` solutionB. `H_(2)` is removed through occlusion with PdC. CO is oxidized to `CO_(2)` with steam in the presence of a catalyst followed by absorption of `CO_(2)` in alkaliD. CO and `H_(2)` are fractionally separated using difference in their densities |
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Answer» Correct Answer - C |
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| 459. |
The rate of physisorption increases withA. decrease in temperatureB. increase in temperatureC. decrease in presssureD. decrease in surface area |
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Answer» Correct Answer - A |
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| 460. |
Rate of physisorption increases with :A. decrease in temperatureB. increase in temperatureC. decrease in temperatureD. decreases in surace area. |
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Answer» Correct Answer - A Rate of physisorption increases with dcreases in temperature because of exothermic nature of the process of adsorption. |
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| 461. |
Rate of physisorption increases with :A. decrease in temperatureB. increases in temperatureC. decrease in pressureD. decrease in surface area |
| Answer» Correct Answer - A | |
| 462. |
Lyophilic sol areA. Irreversible solsB. They are prepared from inorganic compoundC. Coagulated by adding electrolytesD. Self-stabilizing |
| Answer» Correct Answer - D | |
| 463. |
Which is not correct for physical adsorption ?A. Adsorption on solids is reversible.B. Adsorption increases with increase in temperature.C. Adsorption is spontaneousD. Both enthalpy and entropy of adsorption are negative. |
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Answer» Correct Answer - B |
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| 464. |
Given below, catalyst and corresponding process/reaction are matched. The mismatch isA. `[RhCl(P Ph_(3))_(2)]`: HyddrogenationB. `TiCl_(4)+Al(C_(2)H_(5)):` polymerisationC. `V_(2)O_(5)`: Haber-Bosch processD. Nickel:Hydrogenation |
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Answer» Correct Answer - C Factual `(V_(2)O_(5)` is used in contact process). |
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| 465. |
Adsorpton of gases on solid surface is generally exothermic because :A. enthalpy is positiveB. entropy decreasesC. entropy increasesD. free energy increases. |
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Answer» Correct Answer - B Entropy decreases because the molecules of the gas are adsorbd on the surface of adsorbent and energy is released during attraction. |
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| 466. |
Adsorpton of gases on solid surface is generally exothermic because :A. enthalpy is positiveB. entropy decreaseC. entropy increasesD. free energy increase |
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Answer» Correct Answer - b Randomness decrrase during adsorpton . |
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| 467. |
Select correct statements(s).A. Hydrophilic colloid is a colloid in which there is a strong attraction between the dispersed phase and water.B. Hydrophobic colloid is a colloid in which there is a lack of attraction between the dispersed phase and water.C. Hydrophobic sols are often formed when a solid crystallises rapidly from a chemical reaction or a supersaturated solution.D. All of the above |
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Answer» Correct Answer - D |
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| 468. |
Lyophilic sols areA. irreversible solsB. they are prepared from inorganic compoundC. coagulated by adding electrolytesD. self-stabilizing |
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Answer» Correct Answer - D |
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| 469. |
Adsorpton of gases on solid surface is generally exothermic because :A. Enthalpy is positiveB. Entropy decreasesC. Entropy increasesD. Free energy increases |
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Answer» Correct Answer - B When a gas is adsorbed on the surface, the freedom of movement of its molecules becomes restricted. This causes decrease in the entropy of the gas after adsorption, i.e, `DeltaS` becomes negative. |
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| 470. |
Which one of the following statements is false for hydrophilic sols?A. They do not require electrolytes for stabilityB. Their viscosity is of the order of that of waterC. Their surface tension is usually lower than that of dispersion mediumD. None of the above |
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Answer» Correct Answer - B |
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| 471. |
Catalyst used in hydrogention of oils isA. PtB. MoC. FeD. Ni |
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Answer» Correct Answer - D Oil`+H_(2)overset(Ni)to`Ghee. |
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| 472. |
Which one of the following statements is false for hydrophilic sols?A. they do not require electrolytes for stabilityB. their viscosity is less of that of waterC. their surface tension is usually lower than that of despersion mediumD. none of these |
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Answer» Correct Answer - B viscosity of lyophilic colloid is less than water. |
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| 473. |
Lyophilic sols are more stable than lyophobic sols becauseA. Irreversible solsB. They are prepared from inorganic compoundC. Coagulated by adding electrolytesD. Coagulated by adding electrolytes |
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Answer» Correct Answer - D Lyophilic sols are self stabilizing because these sols are reversible and are highly hydrated in the solution. |
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| 474. |
Lyophilic sols are more stable than lyophobic sols because their particles areA. positively chargedB. negatively chargedC. all solubleD. attract each other |
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Answer» Correct Answer - C Lyophilic sols, are more stable than Lyophobic sols because after vaporization its remaining residue , convert into colloidal state after the addition of solvent. |
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| 475. |
Assertion: Deep electric chosk causes death of of an animal. Reason: Electric shock coagulate the blood.A. if both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertionC. If assertion is true but reason is false.D. If the assertion and reason both are false. |
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Answer» Correct Answer - A It is fact that deep electric shock causes death of an animal and the reason for this is that blood is coagulated by electric shock. Therefore, ehere both assertion and reason are true. |
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| 476. |
STATEMENT-1 : According to the lock - and - key model. When the `key` (substrate) fits the `lock` (active site) the chemical change bedins. STATEMENT-2 : Modern X-ray crystallographic and spectroscopic methods show that in many cases, the enzyme changes shape when the substrate lands at the active site. STATEMENT- 3 : Enzyme catalysed reactions processed through a fast, reversible formation of an enzyme substrate complex, followed by a slow conversion to product and free enzyme.A. T F TB. F T TC. T T TD. T T F |
| Answer» Correct Answer - `(3)` | |
| 477. |
Calculate coagulation value of `AlCl_(3)` if for coagulation of 400 ml of a gold sol, 427.2 milli-grams of `AlCl_(3)` is required. |
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Answer» Correct Answer - 8 |
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| 478. |
Calculate the number of sols which are negatively charged. |
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Answer» Correct Answer - 8 |
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| 479. |
Name the four negatively charged sols. |
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Answer» The following are the negatively charged sols. `to` Metal sols Eg : Ag, Au-sols. `to` Acid dye stuffs Eg : eosinsol. `to` Metallic suphides sols Eg : `ArS_(3), CdS` sols. `to` Sols of starch, gum, clay etc. |
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| 480. |
Storng Tyndall effect is observed only when (i) the refractive indices of the dispersed phase and the dispersion medium differ greatly in magnitude (ii) the diameter of the dispersed particles is biggest than the wavelength of the light used (iii) the refractive indices of the dispersed phase and the dispersion medium are similar (iv) the diameter of the dispersed particles is not much smaller than the wavelength of the light used.A. `(i),(ii)`B. `(i),(iv)`C. `(iii),(iv)`D. `(ii),(iii)` |
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Answer» Correct Answer - B The intensity of the scattered light is directly proportional to the difference between the refractive indices of the dispered phase and the disperison medium. In lyophobic sols, the Tyndall effect is strong because this difference is appreciable on account of weak or no intraction between the two phases. While in lypophilic sols the Tyndall effect is much weaker because the particles are largely solvated which lowers the difference in the refractive indices of the two phases. For effective scattering of light, the diameter of the particles should match with the wavelength of the light. |
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| 481. |
All adsorptions occur with release in energy and are found to be exothermic in nature. In an adsorption process, the enthalpy change for adsorption of one_____ of adsorbate on an adsorbent surface is called enthaply or heat of adsorption for the particular adsorption.A. moleB. gramC. gram atomD. gram molecule |
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Answer» Correct Answer - A Enthalpy change is always expressed per mole. Moreover mole is preferred over gram atom or gram molecules as it is a general term. |
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| 482. |
Colloids consist of……….phase, viz, ………….and …………………. . |
| Answer» Correct Answer - Two, dispersed, dispersion | |
| 483. |
Smoke is a colloidal system of dispersed in …………. . This system is temed as…………….. |
| Answer» Correct Answer - Carbon, air, aerosol | |
| 484. |
Blood is a ………… charged sol. |
| Answer» Correct Answer - Negatively | |
| 485. |
A catalyst :A. alters the reaction mechanismB. decreases the activation energyC. increases the average kinetic energy of reacting moleculeD. increases the frequency of collisions of reacting species |
| Answer» Correct Answer - B | |
| 486. |
Which of the following act as a protective colloids?A. GelatinB. Silica gelC. Oil-in-water emulsionD. All correct |
| Answer» Correct Answer - A | |
| 487. |
The stabilization of a dispersed phase in a lyopobic colloid is due toA. The adsorption of charged substances on dispersed phase.B. The large electro-Kinetic potential developed in the colloid.C. The formation of an electrical layer between two phase.D. The viscosity of the medium |
| Answer» Correct Answer - C | |
| 488. |
Egg albumin is :A. Reversible colloidB. Lyophilic colloidC. Protective colloidD. All |
| Answer» Correct Answer - D | |
| 489. |
The most appropriate method of making egg-albumin sol is :A. Keep the egg in boiling water for 10 minutes. After removing the shell, transfer the yellow part of the content to `100 mL` of `5%` w/V saline solution and homogenize with a mechanical shaker.B. Break an egg carefully and transfer the transparent part of the content to 100 mL of `5%` w/V saline solution and stir will.C. Keep the egg in boiling water for 10 minutes. After removing the shell, transfer the white part of the content to 100 mL of `5%` w/V saline solution and homogenize with a mechanical shaker.D. Break an egg carefully and transfer only the yellow part of the content to 100 mL of `5%` w/V saline solution and stir well. |
| Answer» Correct Answer - B | |
| 490. |
Which method of preparation of sol involves chemical reaction?A. HydrolysisB. Mechanical dispersionC. Exchange of solventD. All of these |
| Answer» Correct Answer - A | |
| 491. |
Paste isA. Suspension of solid in a liquidB. Mechanical dispersion of a solid in liquidC. Colloidal solution of a solid in solidD. None of these |
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Answer» Correct Answer - A Suspension of solid in a liquid. |
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| 492. |
The conductivity test is positive forA. O/WB. W/OC. Both (1) & (2)D. None of these |
| Answer» Correct Answer - A | |
| 493. |
Which is an example of auto-catalysis?A. Hydrolysis of methyl acetateB. Oxidation of `Na_(2)SO_(3)` in presence of `Na_(2)AsO_(3)`C. Oxidation of oxalic acid by `KMnO_(4)`D. None of these |
| Answer» Correct Answer - A::C | |
| 494. |
Cloud bursts due to :A. Attraction towards the electrical charges on the earthB. Large amount of water present in the cloudC. Dense clouds are present in upper atmosphereD. Mutual discharge of opportunity charged clouds resulting in the coagulation. |
| Answer» Correct Answer - D | |
| 495. |
What do `x` and `m` represent in the following expression? `(x/m)=KP^(1//n)` |
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Answer» In expression `(x/m)=KP^(1//n)` x=mass of adsorbate , m=mass of adsorbent. In expression `(x/m)=KP^(1//n)` x=mass of adsorbate , m=mass of adsorbent. |
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| 496. |
What type of building blocks are present in the structure of zeolites? What is this structure called? , |
| Answer» The buildings block in the structure of zeolites are truncated octahedral (cubo-octahedra). This structure is called `'beta`-CASE' OR 'sodalite cage' The buildings block in the structure of zeolites are truncated octahedral (cubo-octahedra). This structure is called `'beta`-CASE' OR 'sodalite cage' | |
| 497. |
Freundlich adsorption isotherm is given by the expression `(x)/(m)=kp^((1)/(n))` Which of the following conclusions can be drawn from this expression?A. When 1/n =0, the adsorption is independent of pressure.B. When 1/n = 0, the adsorption is directly proportional to pressure.C. When n = 0, x/m vs p graph is a line parallel to x-axis.D. When n=0, plot x/m vs p is a curve. |
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Answer» Correct Answer - A::C Conclusions can be drawn from the expession. |
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| 498. |
The separation of colloidal particles from the particles having molecular dimensions is known asA. electroosmosisB. electrophoresisC. electrodialysisD. electrolysis |
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Answer» Correct Answer - C Ordinarily, the process of dialysis is quite slow. It can be made faster by applying an electric field if the dissolved substance in the impure colloidal solution is only an electrolyte because the movement of ions across the membrane can be expedited by applying electric potential through two electrodes. This process which is faster than simple dialysis is known as electrodialysis. The colloidal solution is placed in a bag of suitable membrane white pure water is taken outside. Electrodes are fitted in the compartment and ions present in the colloidal solution migrate out to the opposite charged electrodes. |
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| 499. |
The process of separating the colloidal particles from the solvent and solutes present in the collaidal solution by specially prepared filters, which are permerable to all substances excepts the colloidal particles is known asA. selective filtrationB. ultrafiltrationC. graded filtrationD. restricted filtration |
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Answer» Correct Answer - B In this method called ultra-filtration, colloidal sols are purified by carrying out filtration through special type of graded filtras called ultra-filters. These filter papers allow only the electrolytes to pass through. Colloidal particles can pass through ordinary filter paper because the pores are too large. Howener, the pores of filter paper can be reduced in size by impregnating ordinary filter paper with collodion solution to stop the flow of colloidal particles. |
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| 500. |
Which of the following separations is possible due to different adsorption tendencies of the solutes of a solution ?A. chromatographic separationB. gravity separationC. magnetic separetionD. hydraulic separation |
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Answer» Correct Answer - A In chromatography, we separate a mixture of compounds by taking advantage of the different dergrees to which they undergo adsorption |
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