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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.
| 851. |
Collidal dispersion have been classified into different types depending upon the physical state of the dispersed phases and the dispersion medium. They are prepared in the industry or in the laboratory by a number of methods and then purified. The protective action of lyophilic colloids was studied by Zsigmondy and he introduced a term called gold number. In the experiment on electro-osmosis in which of the following the level of the dispersion medium will fall on the cathode side.A. `Fe(OH)_(3)` solB. `As_(2)S_(3)` solC. Gold solD. Starch sol |
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Answer» Correct Answer - A Level on the cathode side will fall when dispersion medium moves towards anode, i.e., dispersion medium carries `-ve` charge or colloidal particles carry the charge, viz., `Fe(OH)_(3)` Correct Answer - A Level on the cathode side will fall when dispersion medium moves towards anode, i.e., dispersion medium carries `-ve` charge or colloidal particles carry the charge, viz., `Fe(OH)_(3)` |
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| 852. |
Collidal dispersion have been classified into different types depending upon the physical state of the dispersed phases and the dispersion medium. They are prepared in the industry or in the laboratory by a number of methods and then purified. The protective action of lyophilic colloids was studied by Zsigmondy and he introduced a term called gold number. Which of the following does not form a lyophilic colloid?A. Rubber dissolved in benzene.B. White or the egg dissolved into water.C. Common salt added into benzene.D. Stannous chloride solution added to gold chloride solution. |
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Answer» Correct Answer - D `SnCl_(2)+AuCl_(3)` react to from gold sol which is a lyophobic sol. Correct Answer - D `SnCl_(2)+AuCl_(3)` react to from gold sol which is a lyophobic sol. |
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| 853. |
Colloidal gold can be prepared by ,A. disinfectantB. Anticancer agentC. Germ killerD. Tonic to raise vitlity of human system |
| Answer» Correct Answer - D | |
| 854. |
The smog is essentially caused by the presence of `:`A. `O_(2) and O_(3)`B. `O_(2) and N_(2)`C. Oxides of sulphur and nitrogenD. `O_(3) and N_(2)` |
| Answer» Correct Answer - C | |
| 855. |
An inhibitor is essentially:A. a negative catalystB. a heterogeneous catalysisC. an auto catalystD. a homogeneous catalyst |
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Answer» Correct Answer - a |
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| 856. |
the process whichh is catalysed by one of the product is calledA. acid - base catalysisB. autocatalysisC. negative cataystD. homogeneous catalysis |
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Answer» Correct Answer - b |
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| 857. |
the stability of lyophilic colloids is due toA. Charge on their particlesB. A layerr of dispersion medium on their particlesC. The smaller size of their particlesD. The large size of their particles |
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Answer» Correct Answer - B Lyophilic possesses solvent loving nature and thus a thin layer of dispersed phase is formed a round sol particles. |
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| 858. |
Milk is an example of :A. Pure solutionB. GelC. EmulsionD. Suspension |
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Answer» Correct Answer - D Milk is the example of emulsion of fat globules in water. |
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| 859. |
Choose the correct statement .A. The ultra-filter allow only the electrolytes to pass through under the influence of pressure or suction pumpB. When an electric field is applied during dialysis , the process is refered to as electrodialysisC. Both (a) and (b) are correctD. None of the above . |
| Answer» Correct Answer - C | |
| 860. |
The migration of positively charged colloidal particles, under an electrical field, towards the cathode is calledA. CataphoresisB. Electro-osmosisC. SedimentationD. Electrodialysis |
| Answer» Correct Answer - A | |
| 861. |
Assertion : `Fe(OH)_(3) and As_(2)S_(3)` colloidal sols on micing fro precipitate. Reason : `Fe(OH)_(3) and As_(2)S_(3)` combine to from precipitate of new compound.A. If both assertion and reason are correct and reason is correct explanation for assertion.B. If both assertion and reason are correct but reason is not correct explanation for assertion.C. If assertion is correct but reason is incorrect.D. If assertion and reason both are incorrect. |
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Answer» Correct Answer - C Correct reason. On mixing `Fe(OH)_(3)` (-ve sol) and `As_(2)S_(3)` (-ve sol) nutual coagulation occurs leading to a precepitation. No new compound is formed. |
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| 862. |
Which of the following statement is incorrect ?A. A colloidal solution is also known as a solB. If the dispersion medium is an organic liquid, the system is termed organosol.C. If the dispersion medium is water the system is termed hydrosol.D. If the dispersion medium is an organic liquid, the system is termed aquasol. |
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Answer» Correct Answer - D The term aquasol is used only if the dispersion medium is water. |
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| 863. |
Liquid-liquid colloidal system is known asA. aerosolB. foamC. emulsionD. gel |
| Answer» Correct Answer - C | |
| 864. |
Which among the following are enzyme catalysts ?A. GlucoseB. AmylaseC. TrypsinD. Nuclease. |
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Answer» Correct Answer - B::C::D are all enzymes. |
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| 865. |
Which is an example of coagulation ?A. curdling of milkB. purification of water by addition of alumC. formation of deltas at the river bedsD. formation of ice |
| Answer» Correct Answer - A::B::C | |
| 866. |
which of the following statements is correct for a lyophilic solution?A. It is not easily solvatedB. The coagulation of this sol is irreversible in natureC. It is unstableD. It is quite stable in a solvent |
| Answer» Correct Answer - D | |
| 867. |
Which of the following are based on Tyndall effect.A. Tail of cometsB. DeltasC. Blue colour of skyD. Coagulation |
| Answer» Correct Answer - A::C | |
| 868. |
Multimolecular colloids are present in :A. sulphur solB. gold solC. protein solD. soap sol. |
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Answer» Correct Answer - A::B are the correct answers. |
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| 869. |
Which of the following are incorrect statements?A. Hardy Schulze rule is related to coagulation.B. Brownian movement and Tyndall effect are the characteristics of colloids.C. In gel, the liquid is dispersed in liquid.D. Higher the gold number, more is the protective power of lyophilic sols. |
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Answer» Correct Answer - C::D |
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| 870. |
Match list I with list II and give the correct answer : |
| Answer» Correct Answer - `(A - p, q) ; (B - r) ; (C - q, t); (D - s); (E - u)` | |
| 871. |
Which of the following are multimolecular colloids?A. Sulphur solB. Egg albumin in waterC. Gold solD. Soap solution |
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Answer» Correct Answer - A::C |
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| 872. |
Which of the following are hydrophobic sols ?A. Protein solB. Gold solC. Gum solD. `Fe(OH)_(3)` sol |
| Answer» Correct Answer - B::D | |
| 873. |
Which of the following statements regarding sols is not correct?A. Brownian movement stablises sols.B. In a reaction, catalyst may change qualitatively as well as physically.C. An emulsion can be broken both by heating as well as freezing.D. On prolonged dialysis, colloids become stable. |
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Answer» Correct Answer - D |
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| 874. |
Match list I with list II and select the correct answer : A. `{:(P, Q, R, S),(3, 4, 1, 2):}`B. `{:(P, Q, R, S),(1, 2, 4, 3):}`C. `{:(P, Q, R, S),(3, 1, 4, 2):}`D. `{:(P, Q, R, S),(2, 3, 1, 4):}` |
| Answer» Correct Answer - C | |
| 875. |
Small liquid droplets in another liquid is calledA. SuspensionB. EmulsionC. GelD. True solution |
| Answer» Correct Answer - B | |
| 876. |
How are colloids classified on the basis of interaction between dispersed phase and dispersion medium ? |
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Answer» Lyophilic colloid: The colloidal solution in which the dispersed phase has great affinity to the dispersion medium is called as Lyophilic colloid or Lyophilic solution. Ex: Starch solution. The starch paste when dissolved in hot water , with stirring , the starch solution is formed. The starch particles (dispersed phase) has great affinity to water molecules (dispersion medium). So starch solution is a lyophilic solution or lyophilic colloid. Lyophilic colloid : The colloidal solution in which there exists not much affinity between the dispersed phase and dispersion medium, it is called a Lyophobic colloid or Lyophobic solution. Ex : Gold solution. Gold rods are placed in water containing alkali. Electric arc is applied between gold rods. The gold particles dissolves in water, to give gold solution. Gold particles (dispersed phase ) have not much affinity towards water (dispersion medium) . So this is a Lyophobic solution or Lyophobic colloid. |
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| 877. |
How are colloids classified on the basis of the nature of interaction between a dispersed phase and a dispersion medium ? Describe an important characteristic of each class. Which of the sols need stabilising agents for preservation ? |
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Answer» The colloids solution in which the dispersed phase has great affinity to the dispersion medium is called a Lyophilic colloid or Lyophilic solution. Ex : Starch solution. The starch paste when dissolved in hot water , with stirring , the starch solution is formed . The starch particles (dispersed phase) has great affinity to water molecules (dispersion medium ). So starch solution is a lyophilic solution or lyophilic colloid Lyophobic colloid : The colloidal solution in which there exists not much affinity between the dispersed phase and dispersion medium , it is called a Lyopholic colloid or Lyophobic solution. Ex : Gold solution. Gold rods are placed in water containing alkali. Electric arc is applied between gold rods. the gold particles dissolves in water, to give gold solution. Gold particles (dispersed phase) have not much affinity towards water (dispersion medium) . So this is a Lyophobic solution or Lyophobic colloid. Lyophilic colloidals are much stable than lyophobic colloids . A very amount of electrolyte can precipitate the lyophobic colloids. But their precipitation can be prevented by the addition of small amounts of lyophilic colloids. This lyopilic colloids form a protecting layer around the lyophobic colloids and protect them from precipitation (coagulation). Lyophilic colloids used for this purpose are called protective colloids. Ex : Gelatin, gum, starch sols are generally used as protective colloids. |
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| 878. |
Which of the following has minimum flocculation value :-A. `Pb^(2+)`B. `Pb^(4+)`C. `Sr^(2+)`D. `Na^(+)` |
| Answer» Correct Answer - B | |
| 879. |
All colloidal solutions show :A. Very high osmotic pressureB. High omotic pressureC. Low osmotic pressureD. No osmotic pressure |
| Answer» Correct Answer - C | |
| 880. |
Gold number is a measure ofA. The amount of gold present in the colloidal solution.B. The amount of gold required to break the colloid.C. The amount of gold required to protect the colloid.D. None of the above |
| Answer» Correct Answer - D | |
| 881. |
The capacity of an ion to coagulate a colloidal solution depends onA. Its shapeB. The amount of its chanrgeC. The sign of the chargeD. Both, the amount and the sign of the charge |
| Answer» Correct Answer - D | |
| 882. |
How emulsions are classified ? Give one example for each type of emulsion. |
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Answer» Emulsion : The colloidal system in which a dispersion of finely divided droplets of a liquid in another liquid medium is called Emulsion. Ex : Milk In Milk, the droplets of liquid fat are dispersed in water. This is an example for oil in water type emulsion. Classification of emulsions : Emulsions are classified into two classes. These are a) oil in water (O/W) and b) water in oil (W/O), (O = Oil, W = Water). These emulsions are classified as such depending on which is dispersed phase and which is dispersion medium.a) Oil in Water (O/W) type emulsions : tn this type of emulsions, the disperse d phase is and the dispersion medium is water.Ex : Milk, liquid, fat (oil) in water. Vanishing cream, fat in water. b) Water in Oil (W/O) type emulsions : In this type of e mulsions, the dispersed phase is water and the dispersion medium is oil. Ex : Stiff greases water in lubrication oils Cod liver oil water in cod liver oil Cold cream water in fat of Emulsions : Emulsions are useful `to` In the digestion of fats in intestines. `to` In washing processes of clothes and crockery. `to` In the preparation of lotions, creams, ointments in pharmaceutical and cosmetics. `to` In the extraction of metals (froth flotation). `to` In the conversion of cream into butter by churning. `to` To break oil and water emulsions in oil wells. `to` In the preparation of oily type of drugs for easy adsorption to the body. |
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| 883. |
The capacity of an ion to coagulate a colloidal solution depends onA. the magnitude of charge onlyB. its size onlyC. both the size of ion and the magnitude of charge in itD. both sign and magnitude of charge. |
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Answer» Correct Answer - D Different electolytes have different coagulation values.The coagulation behaviour of various elecrolytes was studied in detail by Hardy and Schulze. They found that `(1)` the ions carrying charge opposite to that of sol particles are effective in causing the coagulation of the sol. `(2)` coagulating power of an electrolyte is directly proportional to the fourth power of the valency of the ions causing coagulation. Thus,for the coagulation of sols carrying negative charge (like `As_(2)S_(3)` Sol), `Fe^(3+)` ions are more effective than `Ba^(2+)` or `Na^(+)` ions .Similarly, for the coagulation of sols carrying positive charge (such as `Fe(OH)_(3)` sol), `PO_(4)^(3-)` ions are more efficient than `SO_(4)^(2-)` or `Cl^(-)` ions. The two observations given above are collectively called Hardy-Schulze rule. These observations show that utmost care should be taken to keep sols away from environment containing even small amount of elecrolytes. |
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| 884. |
Which of the following sols are relativity difficult to coagulate?A. (i), (iii)B. (ii), (iii)C. (i), (ii)D. (iii), (iv) |
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Answer» Correct Answer - B Because there are two factors which are responsible for the stability of lyophilic sols. These factors are the charge and solvation of the colloidal particles. When these two factors are removed a lyophilic sol can be coagulated. This is done (i) by adding an electrolyte and (ii) by adding a suitable solvent. When solvents such as alcohol and acetone are addsd to hydrophilic sols, the dehyration of dispersed phase occurs. Under this condition a small quantity of electrolyte can bring about coagulation. |
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| 885. |
smoke precipitator work on the principal of :A. centrifugationB. neutralization of charge on colloidsC. absorptionD. addition of electrolytes |
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Answer» Correct Answer - b |
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| 886. |
Which of the following is a protective colloid?A. GelatineB. Potato starchC. Egg albumenD. All of these |
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Answer» Correct Answer - D Lyophilic sols are more stable than lyophobic sols. This is due to the fact that lyophilic colloids are extensively solvated, i.e. their colloidal particles are covered by a sheath of the liquid in which they are dispersed. Lyophilic colloids have a unique property of protecting lyophobic colloids. When a lyophilic sol is added to the lyophobic sol, the lyophilic particles form a layer around lyophobic particles and thus protect the latter from electrolytes. Lyophilic colloids use for this purpose are called protective colloids. Gelatine, potato strach and egg albumen are typical examples of lyophilic colloids. |
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| 887. |
`3.6` gram of oxygen is adsorbed in `1.2g` of metal powder. What volume of oxygen adsorbed per gram of the adsorbent at `STP` ?A. `0.19Lg^(-1)`B. `1 Lg^(-1)`C. `2.1Lg^(-1)`D. none of these |
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Answer» Correct Answer - 3 Mass of `O_(2)` per gram of adsorbent `=(3.6)/(1.2)=3` No. of moles of `O_(2)` per gram of adsorbent `=(3)/(32)` Volume of `O_(2)` per gram of adsorbent `=(3)/(32)xx(0.082.273)/(1)=2.10` |
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| 888. |
A catalyst is used in a reaction toA. Change the nature of reaction productsB. Increase the reaciton yieldC. Decreased the need for reactantsD. Decrease the time required for the reaction |
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Answer» Correct Answer - D A catalyst is used to decrease the time required for the reaction hence it can decease or increase the rate of reaction. |
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| 889. |
Which of the following is wrong`:`A. Enthalpy ( numerical value ) of physisorption is greater than that of chemisorptionB. Physisorption is not very specific but chomisorption is highly specificC. Chemisorption takes place at relatively high temperaturesD. In physisorption generally multi`-` molecular layers are formed on the adsorbent |
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Answer» Correct Answer - 1 from the knowledge of two types of adsorptions. |
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| 890. |
select incorrect statementA. soap and detergent lower the interfacil surface tension between oil and waterB. Basic pricniple of peptization is reverse of coagulationC. soap and detergent used as emulsifersD. Lyophilic sols need stabilizing agent |
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Answer» Correct Answer - d |
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| 891. |
Below critical micelle concentration (CMC):A. the surfactant molecules of ions undergo association to form clustersB. the viscosity of solution increases abruptlyC. subtances like grase , fat , etc. dissolve colloidallyD. salt behave as normal , strong electrolyte. |
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Answer» Correct Answer - d |
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| 892. |
Match list I with list II and select the correct answer : A. `{:(P,, Q,, R,, S),(3,, 4,, 1,, 2):}`B. `{:(P,, Q,, R,, S),(1,, 2,, 4,, 3):}`C. `{:(P,, Q,, R,, S),(3,, 3,, 2,, 1):}`D. `{:(P,, Q,, R,, S),(2,, 3,, 1,, 4):}` |
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Answer» Correct Answer - C `{:(P., "Coagulation is known as accomulation of collidal sols."),(Q., "Dialysis is purification of colloids".),(R., "Peptization is formation of colloidal solution from precipitates".),(S., "Tyndall effect is scattering of light by colloidal particle".):}` |
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| 893. |
Which of the following is not represented by sols?A. AdsorptionB. Tyndall effectC. FlocculationD. Paramagntism |
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Answer» Correct Answer - d |
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| 894. |
If liquid is dispersed in solid medium, then this is called as:A. SolB. EmulsionC. Liquid aerosolD. Gel |
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Answer» Correct Answer - D It is factual statement. |
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| 895. |
A catalyst increase rate of reaction by :A. decreasing enthalpyB. decreasing internal energyC. decreasing activation energyD. increasing activation energy |
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Answer» Correct Answer - C |
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| 896. |
Which of the following relations is (are) correct according to Freundlich ? (i) x/m = constant (ii) x/m = constant `xx p^(1//n) (n gt 1)` (iii) x/m = constant `xx p^(n) (n gt 1)`A. All are correctB. All are wrongC. (ii) is correctD. (iii) is correct |
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Answer» Correct Answer - C According to Freundlich adsorption isotherm, `(x)/(m) prop kp^(1//n) (n gt 1).` |
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| 897. |
Which of the following is correct about lyophilic sold?A. They are irreversibleB. They are formed by inorganic substancesC. They are readily coagulated by addition of electroylstesD. They are self stabilized |
| Answer» Correct Answer - 4 | |
| 898. |
Which one is false in the following statement?A. A catalyst is specific in its actionB. A very small amount of the catalyst alters the rate of a reactionC. The number of free vacancies on the surface of the catalyst increases on sub-divisionD. Ni is used as a catalyst in the manufacture of ammonia. |
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Answer» Correct Answer - D |
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| 899. |
Freundlich equation for adsorption of gases (in amount of Xg) on a solid (in amount od mg) at constant temperature can be expressed asA. log `(X)/(m)=logP+(1)/(n)logK`B. log `(X)/(m)=log.K+(1)/(n)logP`C. `(X)/(m)propP^(n)`D. `(X)/(m)=logP+(1)/(n)logK` |
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Answer» Correct Answer - B `(X)/(m)propP^(1//n)` or `(X)/(m)=KP^(1//n)` Taking log on both sides. `log.(X)/(m)=logK+(1)/(n)logP` |
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| 900. |
Which of the following parameter is correct regarding adsorption of gases over solid?A. `DeltaS_("system") gt 0`B. `DeltaS_("surrounding") gt 0`C. `DeltaG gt 0`D. `DeltaH gt 0` |
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Answer» Correct Answer - B |
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