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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.
| 1301. |
Arsenic sulphide forms a sol with a negative charge. Which of the following ionic substances should be most effective in coagulating the sol?A. KClB. `MgCl_(2)`C. `Al_(2)(SO_(4))_(3)`D. `Na_(3)PO_(4)` |
| Answer» Correct Answer - C | |
| 1302. |
Brownian motion is a/anA. Electrical propertyB. Mechanical propertyC. Optical propertyD. Colligative property |
| Answer» Correct Answer - B | |
| 1303. |
Which of the following is most effective in coagulating a ferric hydroxide sol ?A. `KCl`B. `KNO_(3)`C. `K_(2)SO_(4)`D. `K_(3)[Fe(CN)_(6)]` |
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Answer» Correct Answer - D `K_(3)[Fe(CN)_(6)]` is most effective in coagulating a ferric hydroxide sol. |
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| 1304. |
Which of the following is most effective in coagulating a ferric hydroxide sol ?A. `KCl`B. `KNO_(2)`C. `K_(2)SO_(4)`D. `K_(3)[Fe(CN)_(6)]` |
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Answer» Correct Answer - D Effectiveness of coagulation by electrolyte `prop` charge on coagulating ion. |
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| 1305. |
Which of the following is most effective in coagulating a ferric hydroxide sol ?A. KClB. `KNO_(3)`C. `K_(2)SO_(4)`D. `K_(3)[Fe(CN)_(6)]` |
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Answer» Correct Answer - D `K_(3)[Fe(CN)_(6)]` is most effective in coagulating a ferric hydroxide sol. |
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| 1306. |
a negatively chaged suspension of clay in water will need for precipitation the minimum amount ofA. Aluminium chlorideB. Potassium sulphateC. sodium hydroxideD. Hydrochloric acid |
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Answer» Correct Answer - A Negatively charged sols require minimum amount of electrolyte having higher valence of cation. |
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| 1307. |
Among the following, which surfactant will form micelles in aqueous solution at the lowest molar concentration at ambient conditions?A. `CH_(3)(CH_(2))_(15)N^(+)(CH_(3))_(3)Br^(-)`B. `CH_(3)(CH_(2))_(11)OSO_(3)^(-)Na^(+)`C. `CH_(3)(CH_(2))_(6)COO^(-)Na^(+)`D. `CH_(3)(CH_(2))_(11)N^(+)(CH_(3))_(3)Br^(-)` |
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Answer» Correct Answer - A |
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| 1308. |
Among the following , the surfactant that will form micelles in aqueous solution at the lowest molar concentration at amibemt conditions, is :A. `CH_(3)(CH_(2))_(15)N^(+)(CH_(3))_(3)Br^(-)`B. `CH_(3)(CH_(2))_(11)OSO_(3)^(-)Na^(+)`C. `CH_(3)(CH_(2))_(6)COO^(-)Na^(+)`D. `CH_(3)(CH_(2))_(11)N^(+)(CH_(3))_(3)Br^(-)` |
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Answer» Correct Answer - A The surfactant cetyl trimethylammonium bromide `CH_(3)(CH_(2))_(15)N^(+)(CH_(3))_(3)Br^(-)` with maximum molecular mass will form micelle at the lowest CMC. |
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| 1309. |
Why is ferric hydroxide colloid positively charged when prepared by adding ferric chloride to hot water ?A. Due to precipitation of ferric hydroxide there is an excess of `Fe^(3+)` ions.B. Due to preferential adsorption of `Fe^(3+)` ions by the sol of `Fe(OH)_(3)`.C. Due to absence of any negatively charged ion.D. Due to adsorption of `OH^(-)` and `Cl^(-)` ions, the remaining sol has only `Fe^(4+)` ions. |
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Answer» Correct Answer - B The adsorption of positively charged `Fe^(3+)` ions by the sol of hybrated ferric oxide results in positively charged colloid. |
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| 1310. |
Aluminium hydroxide forms a positively charged sol. Which of the following ionic substances should be most effective in coagulating the sol?A. `NaCl`B. `CaCl_(2)`C. `Fe_(2)(SO_(4))_(3)`D. `K_(3)PO_(4)` |
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Answer» Correct Answer - D `Al(OH)_(3)` is positively charged sol. `K_(3)PO_(4)` has greater negative charge. Hence, it is most effective in coagulation of `AlOH)_(3)` sol. |
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| 1311. |
which of the following is most effective in coagulating ferric hydroxide sol? a. `KCl` b. `FeCl_(3)` c. `Na_(2)SO_(4)` d. `K_(3)[Fe(CN)_(6)]` |
| Answer» Since `Fe(OH)_(3)` sol is positively charged, the anion having highest charge will be the most effective, i.e., `[Fe(CN)_(6)]^(3-)` Since `Fe(OH)_(3)` sol is positively charged, the anion having highest charge will be the most effective, i.e., `[Fe(CN)_(6)]^(3-)` | |
| 1312. |
Which one of the following acts as the best coagulating agent for ferric hydroxide sol?A. Potassium ferrocyanideB. Potassium chlorideC. Potassium oxalateD. Aluminium chloride |
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Answer» Correct Answer - A The efficiency of coagulation of an electrolyte depends upon its valency. Thus `[Fe(CN)_(6)]^(4-)` is the best coagulating agent for `Fe(OH)_(4-)` is the best coagulating agent for `Fe(OH)_(3)` sol. |
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| 1313. |
Ferric hydroxide sol is positively charged colloid. The coagulating power of `NO_(3)^(-)` and `PO_(4)^(3-)` ions would be in the orderA. `NO_(3)^(-) gt SO_(4)^(2-) gt PO_(4)^(3-)`B. `SO_(4)^(2-) gt NO_(3)^(-) gt PO_(4)^(3-)`C. `PO_(4)^(3-)gtSO_(4)^(2-)gtNO_(3)^(-)`D. `NO_(3)^(-) = SO_(4)^(2-) = PO_(4)^(3-)` |
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Answer» Correct Answer - C According to Hardy-schulze rule the ions having opposite charge to sol particel cause coagulation and greater the valency of oppositely charged ion more is the coagulating power `(PO_(4)^(3-) gt SO_(4)^(2-) gt NO_(3)^(-))`. |
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| 1314. |
Which of the following solutions having same concentration will have lowest `pH` value?A. KClB. `MgCl_(2)`C. `AlCl_(3)`D. `Na_(3)PO_(4)` |
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Answer» Correct Answer - C `As_(2)S_(3)` is a negatively charged sol. To cause its coagulation , the ions must be positively charged. Greater the magnitude of positive charged, greater will be its coagulating power. Thus `AlCl_(3)` containing `Al^(3+)` ion will be most effective in causing coagulation of `As_(2)S_(3)`. |
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| 1315. |
Which of the following is most effective in causing the coagulation of ferric hydroxide sol :-A. KClB. `KNO_(3)`C. `K_(2)SO_(4)`D. `K_(3)Fe(CN)_(6)` |
| Answer» Correct Answer - D | |
| 1316. |
Which of the following is the most effective in c ausing coagulation of ferric hydroxide sol ?A. KClB. `KNO_(3)`C. `K_(2)SO_(4)`D. `K_(3)[Fe(CN)_(6)]` |
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Answer» Correct Answer - D `Fe(OH)_(3)` is a positive sol. `K_(3)[Fe(CN)_(6)]` with travalent anion is most effective in causing coagulation of this sol. |
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| 1317. |
Ferric hydroxide sol is more readily conagulated by `Na_(3)PO_(4)` in comparison to KCl. Why ?A. mass of `Na_(3)PO_(4)` is more than KCl hence it is more effective than KClB. phosphate ion `(PO_(4)^(3-))` has higher negative charge than `Cl^(-)` ion hence are more effective for coagulationC. KCl is more soluble than `Na_(3)PO^(4)` hence has effective for coagulationD. `Na^(+)` ions are more effective than `K^(+)` ions for coagulation. |
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Answer» Correct Answer - B Ferric hydroxide is a positively charged sol hence ions carrying negative charge can coagulate it. Since `PO_(4)^(3-)` has higher negative charge than `Cl^(-)` hence it is more effective for coagulation. |
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| 1318. |
Match the following `{:(" Column -I"," Column -II "),("(A) Paint"," (p) Solid in dispersed phase"),("(B) Gem stones", " (q) Solid as dispersion medium"),("(C) Cheese"," (r) Liquid as dispersion medium"),("(D) Milk"," (s) Liquid in dispersed phase"):}` |
| Answer» Correct Answer - A(r, s), B(p, q), C(q, s), D(r, s) | |
| 1319. |
How does the precipitation of colloidal smoke take place in Cottrell precipitator? |
| Answer» In Cottrell precipitator, smoke particles (charged) are passed through a chamber containing plates with charge opposite to the smoke particles, smoke particles lose their charge on th plates and get precipitated. | |
| 1320. |
How will you distiguish between dispersed phase and dispersion medium in an emulsion ? |
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Answer» To distinguish between dispersed phase and dispersion medium we increase the concentration of any one dispersion medium or dispersed phase then notice the change. When dispersion medium is added to an emulsion, it gets diluted to any extent. But on adding dispersed phase it forms a separate layer, if added in excess. |
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| 1321. |
In an adsorption experiment, a graph between log `(x/m)` versus log `P` was found to be linear with a slope of `45^(@)` . The intercept on the log y axis was found to be `0.301` . Calculate the amount of the gas adsorbed per gram of charcoal under a pressure of `3.0` atm.A. 4B. 2C. 6D. 8 |
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Answer» Correct Answer - C log `(x)/(m)=logK+(1)/(n)logP` `:.` Plot of log `(x)/(m)` versus log `P` is linear with slope `=(1)/(n)` and intercept `=logK` Thus `(1)/(n)=tantheta=tan45^(@)=1` or `n=1` log `K=0.301` or `K=` antilog `0.301=2` At `P=3atm` `(x)/(m)=KP^(1//n)=2xx(3)^(t)=6` |
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| 1322. |
Size of colloidal particles varies fromA. `10^(-9)` to `10^(-7)`mB. `10^(-17)` to `10^(-9)m`C. `10^(-7)` to `10^(-5)` mD. `10^(-10)` to `10^(-4)`m |
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Answer» Correct Answer - A Colloidal particles range between `10^(-9)` to `10^(-7)m` or `10^(-7)` to `10^(-5)cm`. |
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| 1323. |
`10^(-4)g` of gelatian is required to be added to `100cm^(23)` of a standard gold sol to just prevent its coagulation by the addition of `1cm^(3)` of `10%NaCl` solution to it. Hence the gold number of gelatain isA. `10`B. `1.0`C. `1`D. `0.01` |
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Answer» Correct Answer - D Gold number is the number of milligrams of a lyophilic colloid that will just prevent the precipitation of `10mL` of a gold sol on the addition of `1mL` of `10%` sodium chloride solution. `100cm^(3)` (0r `100mL`) of gold sol required `10^(-4)g` of gelatin. Thus, the amount of gelating needed to protect `10mL` (or `10cm^(3)`) of gold sol will be `(10^(-4)xx10)/(100)=10^(-5)g` `=(10^(-5)g)((1000mg)/(1g))` `=10^(-2)mg` |
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| 1324. |
A clear solution which is again converted into colloidal solution, the process is calledA. PeptizationB. Electro additionC. ElectrophoresisD. None of these |
| Answer» Correct Answer - D | |
| 1325. |
In an adsorption experiment, a graph between log `(x/m)` versus log `P` was found to be linear with a slope of `45^(@)` . The intercept on the log y axis was found to be `0.301` . Calculate the amount of the gas adsorbed per gram of charcoal under a pressure of `3.0` atm. |
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Answer» Correct Answer - 6 `log((x)/(m))=logK+(1)/(n)logP` `therefore`plot of `log((x)/(m))` versus log P is linear with slope `=(1)/(6)` and intercept `=log " "K` Thus `(1)/(n)=tantheta=tan45^(@)=1" or "n=1` `log" "K=0.301" or "K="antilog "0.301=2` At `P=3` atm `(x)/(m)=KP^(1//n)=2xx(3)^(1)=6` |
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| 1326. |
The coagulation of `100 mL` of a colloidal solution of gold is completely prevented by the addition of `0.030 g` of it before adding `1 mL` of `10% NaCl` solution. Find out the gold number of starch? |
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Answer» Correct Answer - 3 Haemoglobin added to 100 mL of gold sol to prevent coagulation by 1 mL of 10% NaCl sol=0.03g=30mg Haemoglobin requried to be added to 10mL of gold sol to prevent coagulation by 1mL of 10% NaCl sl=3mg. Therefore, gold number of gaemoglobin=3 |
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| 1327. |
Gold numbers of protective colloids A,B,C and D are `0.05,0.01,1.10 and 0.005` respectively. The correct order of their protective powers isA. `CltBltDltA`B. `AltCltBltD`C. `BltDltAltC`D. `DltAltCltB` |
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Answer» Correct Answer - B gold number`prop(1)/("protoective power")` |
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| 1328. |
Colloidal solutions are purified by dialysis. (r) In the process of dialysis, colloidal particles pass through parchment paper.A. Solvent loving solB. Dispersed phaseC. Ions of electrolytesD. Particles of dispersion medium |
| Answer» Correct Answer - C | |
| 1329. |
The colloidal solutions of gold prepared by different methods have different colors due to :A. variable valency of goldB. different concentration of gold particlesC. different types of impuritiesD. different diameter of colloidal particles |
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Answer» Correct Answer - D Colloidal particles of different size scatter light of different wavalengths resulting in different colours. |
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| 1330. |
The colloidal solutions of gold prepared by different methods have different colors due to :A. difference in the size of colloidal particlesB. the fact that gold exhibits variable valancyC. Different concentration of goldD. Presence of different types of foreign particles |
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Answer» Correct Answer - A The colour of any sol depends on its particle size and shape. Au sol is red if particles are spherical and blue if they are disc like. |
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| 1331. |
Some substances behave as electrolytes in dilute solutions and as colloids in their concentrated solutions. Their colloidal forms are sait to formA. EmulsionsB. GelsC. MicellesD. Sols |
| Answer» Correct Answer - C | |
| 1332. |
If the dispersed phase is a liquid and the dispersion medium is a solid, the colloid is known as:-A. A solB. An emulsionC. A gelD. A foam |
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Answer» Correct Answer - C `underset(("Dispersed phase"))("Liquid")+underset(("Dispersion medium"))("Solid")=underset(("Colloid"))(Gel)` (e.g. butter) |
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| 1333. |
The colloidal solutions of gold prepared by different methods have different colors due to :A. variable valency of goldB. different concentration of gold particlesC. Different types of impuritiesD. Different radius of colloidal particles |
| Answer» Correct Answer - D | |
| 1334. |
The gold numbers of some colloidal solutions are given below : `{:("Colloidal Solution","Gold number"),(A,0.01),(B,2.5),(C,20):}` The projetive powers of these colloidal solutions follow the order :A. CgtBgtAB. AgtBgtCC. A=B=CD. BgtAgtC |
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Answer» Correct Answer - B Higher is the gold number, lower will be the protective power. |
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| 1335. |
Which of the following is not a characteristic of chemisorption?A. `DeltaH` is of the order of 400 kJB. Adsorption is irreversibleC. Adsorption may be multimolecular layerD. Adsorption is specific |
| Answer» Correct Answer - C | |
| 1336. |
Which of the following is not a characteristic of chemisorption?A. It is irreversibleB. It is specificC. It is multilayer phenomenonD. heat of adsorption is generally around 80 - 240 kJ |
| Answer» Correct Answer - A::B::D | |
| 1337. |
Which of the following is not a characteristic of chemisorption?A. It is irreversibleB. It is specificC. It is multilayer phenomenonD. Heat of adsorption is about - 400 kJ |
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Answer» Correct Answer - A::B::D |
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| 1338. |
Which of the following is not a characteristic of chemisorption?A. It is reversibleB. It is specificC. It is multilayerD. Heat of adsorption is about `400kJ` |
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Answer» Correct Answer - C |
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| 1339. |
Which of the following is not a characteristic of chemisorption ?A. It is irreversibleB. It is specificC. It is multilayer phenomenonD. Heat of adsorption is of about -400kJ |
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Answer» Correct Answer - C Chemisorption is irreversible , specific , heat of adsorption is of about -400 kJ. |
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| 1340. |
coagultion is the process by which the dispersed phase of a colloid is made to aggregate and thereby separtate from the continuous phase. The minimum concetration of an eletrolyte in milli-moles per litre of the electrolyte solution which required to cause the caogultion of colloidal sol is called coagution value . therefroe higher is the coagulatings power of effective ion, smaller will be the coagultion value of the electrolyte.`As_(2)S_(3)`sol si negatively charged. Capacity to perciopitate of a given colloid depends upon :A. `K_(2)SO_(4)`B. `Na_(3)PO_(4)`C. `AlCl_(3)`D. `CaCl_(3)` |
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Answer» Correct Answer - c |
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| 1341. |
A metal is in the form of dispersed phase and water is the dispersion medium. The colloid is termed as…………….. |
| Answer» Correct Answer - Hydrophobic | |
| 1342. |
coagultion is the process by which the dispersed phase of a colloid is made to aggregate and thereby separtate from the continuous phase. The minimum concetration of an eletrolyte in milli-moles per litre of the electrolyte solution which required to cause the caogultion of colloidal sol is called coagution value . therefroe higher is the coagulatings power of effective ion, smaller will be the coagultion value of the electrolyte.the ability of an ion to bring about coagulation of a given colloid depends upon :A. Its sizeB. The magnitude of its charge onlyC. The sign of its charge onlyD. The sign of its charge |
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Answer» Correct Answer - D The ability of an ion to bring about coagulation fo a given colloid depend upon both the magnitude and sign of its charge. |
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| 1343. |
coagultion is the process by which the dispersed phase of a colloid is made to aggregate and thereby separtate from the continuous phase. The minimum concetration of an eletrolyte in milli-moles per litre of the electrolyte solution which required to cause the caogultion of colloidal sol is called coagution value . therefroe higher is the coagulatings power of effective ion, smaller will be the coagultion value of the electrolyte.the ability of an ion to bring about coagulation of a given colloid depends upon :A. the sign of its chargeB. magnitude of its chargeC. both magnitude and sighD. none of these |
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Answer» Correct Answer - c |
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| 1344. |
Which of the following gases is adsorbed most by activated charcoal?A. `N_(2)`B. `H_(2)`C. `CO_(2)`D. `CH_(4)` |
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Answer» Correct Answer - C The amount of gas adsorbed by a solid depends on the nature of gas. More easily liquefiable gas, i.e., gases with higher critical temperature are readily adsorbed as Vander waals forces are stronger near the critical temperature. `{:(Gas:,N_(2),H_(2),CO_(2),CH_(4)),(T_(C)(H):,126,33,304,190):}` |
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| 1345. |
Which of the following is not a characteristic of chemisorption?A. Adsorption is specificB. Heat of adsorption is of the order of 200 KJ `"mol"^(-1)`C. Adsorption is irreversible.D. Adsorption may be multimolecular layers. |
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Answer» Correct Answer - D Chemisorption forms unimolecular or one layer. |
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| 1346. |
Which of the following gases is adsorbed most by activated charcoal?A. `SO_(2)`B. `CH_(4)`C. `H_(2)`D. All are equally adsorbed |
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Answer» Correct Answer - A Gases with higher critical temperatures are readily adsorbed. Thus `1gram` of activated charcoal adsorbs more `SO_(2)` (critical temp.`630K`) than methane (critical temp `190K`) which is still more than dhiydrogen (critical temperature `33K`). Notice that the value of critical temop-erature isd directly related to the molar mas of gas. |
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| 1347. |
Which of the following gases is adsorbed most by activated charcoal?A. `N_(2)`B. `SO_(2)`C. `H_(2)`D. `O_(2)` |
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Answer» Correct Answer - B Easily liquefiable gases like `SO_(2), NH_(3) CO_(2)` are adsorbed to a greater extent than the elemental gases like `N_(2),O_(2),H_(2)`. |
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| 1348. |
Which of the following colloidal sols are prepared by shaking the lyophilic material with dispersion medium? (i) Gelatin , (ii) Gum (iii) Starch , (iv) Egg albuminA. `(i),(iv)`B. `(ii),(iii),(iv)`C. `(i),(ii),(iii),(iv)`D. `(i),(ii),(iii)` |
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Answer» Correct Answer - C All these are examples of lyophilic sols. They are quite stable and can be easily prepared by shaking the lyophilic material with dispersion medium. |
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| 1349. |
coagultion is the process by which the dispersed phase of a colloid is made to aggregate and thereby separtate from the continuous phase. The minimum concetration of an eletrolyte in milli-moles per litre of the electrolyte solution which required to cause the caogultion of colloidal sol is called coagution value . therefroe higher is the coagulatings power of effective ion, smaller will be the coagultion value of the electrolyte.the coagulation of colloidal particles fo the sol can be caused by :A. heatingB. adding electrolyteC. adding oppositely charged solD. all of these |
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Answer» Correct Answer - d |
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| 1350. |
Which of the following gases is adsorbed most by activated charcoal?A. HClB. `NH_(3)`C. `O_(2)`D. `CO_(2)` |
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Answer» Correct Answer - C It has been found that more readily liquefiable gases are adsorbed more than permanent gases. |
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