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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.
| 251. |
Which one of the following ores is not concentrated by froth floatation process ?A. Copper pyratesB. PentalanditeC. PyrolusiveD. Zinc blende |
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Answer» Correct Answer - C Pyrolusite (`MnO_2` is not concentrated by froth floatation process. |
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| 252. |
Sulphide ore of copper can be concentrated by froth floatation process.A. floatation processB. electromagnetic processC. gravity separationD. distillation |
| Answer» Correct Answer - A | |
| 253. |
Which of the following ores is best concentrated by froth floatation methodA. MalachiteB. CassiteriteC. GalenaD. Magnetite |
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Answer» Correct Answer - C Argentite (`Ag_(2)S`)_ being a low grade ore is preferrably extracted by leaching with NaCN. |
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| 254. |
Pb and Sn are extracted from their chief ore byA. carbon reductioin and self reductionB. self reductionC. electrolysis and self reductionD. self reduction and electrolysis. |
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Answer» Correct Answer - B `2Cu_(2)O` + `Cu_(2)S` `rarr` 6Cu + `SO_2` |
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| 255. |
The chief ore of zinc isA. CryoliteB. CalciteC. CalamineD. Cuprite |
| Answer» Correct Answer - C | |
| 256. |
The most abundant metal on the surface of the earth isA. FeB. AlC. CaD. Hg |
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Answer» Correct Answer - B Al is the most abundant metal on the surface of the earth. |
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| 257. |
The chief source of iodine, in which it is present as sodium iodate, isA. CarnallieB. Sea weedsC. CalicheD. Iodine never exists as sodium iodate. |
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Answer» Correct Answer - C Caliche (chile-salt-peter) contains 0.5 % sodium iodate. |
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| 258. |
The purpose of smelting an ore isA. to oxidise itB. to reduce itC. to separate volatile impuritiesD. to obtain an alloy |
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Answer» Correct Answer - B Smelting of an ore is done to reduce it to give metal. |
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| 259. |
The principal reaction in the zone of heat absorption of blast furnace employed in the metallurgy of iron isA. `2C + O_(2) to CO`B. `2CO + O_(2) to 2CO_(2)`C. `CaCO_(3) underset(-CO_(2))to CaO underset(+SiO_(2))to CaSiO_(3)`D. `C+O_(2) to CO_(2)` |
| Answer» Correct Answer - C | |
| 260. |
The principal reaction in the zone of fusion of blast furnace employed in the metallurgy of iron isA. `C+O_(2) to CO_(2)`B. `2C+O_(2) to 2CO`C. `CO_(2) + C to CO`D. `Fe_(2)O_(3) + 3CO to 2Fe + 3CO_(2)` |
| Answer» Correct Answer - A | |
| 261. |
What is the hydrometallurgy of silver or gold commonly known as ? |
| Answer» Cyanide process. Also, Mac Arthur Forrest cyanide process. | |
| 262. |
Write the names and formulate of main ores of `Fe`, `Cu`, `Al` and `Zn`. |
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Answer» `Fe-"Haematite"-Fe_(2)O_(3)` `Cu-"Copper pyrites"-CuFeS_(2)` `Al-"Bauxite"-Al_(2)O_(3)*2H_(2)O` `Zn-"Zinc blende"-ZnS` |
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| 263. |
Name and formulate the reagent used for the leaching of argentite. |
| Answer» `NaCN`, sodium cyanide | |
| 264. |
In the equation , 4M + `8CN^(-)` + `2H_(2)O` + O `rarr` `4[M(CN)_2]^(-)` + `4OH^(-)` , the metal isA. CopperB. IronC. GoldD. Zinc |
| Answer» Correct Answer - C | |
| 265. |
Froth floatation process is used for the metallurgy ofA. Chloride oresB. AmalgamsC. Oxide oresD. Sulphide ores. |
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Answer» Correct Answer - D Froth floatation process is used for the metallurgy of sulphide ores. |
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| 266. |
In the extractionof iron, slag is produced. Slag isA. COB. `FeSiO_3`C. `MgSiO_3`D. CaSiO_3` |
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Answer» Correct Answer - D In the extraction of iron, lime stone which acts as flux, decomposes at 1073 K to form CaO which then combines with silica to form slag. `CaCO_3` `rarr^(1073 K)` CaO + `CO_2` CaO + `SiO_2` `rarr` `CaSiO_3` |
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| 267. |
Pyrousite is an ore ofA. MagnesiumB. MaganeseC. ZincD. Iron |
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Answer» Correct Answer - B Pyrolusite `(MnO_2` ) is an ore of Mn. |
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| 268. |
The metal found always in the free state , isA. GoldB. SilverC. CopperD. Sodium. |
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Answer» Correct Answer - A Gold (noble metal) occur in native state see Q.1 |
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| 269. |
Which of the following process is used in the extractive metallurgy of magnesium ?A. Fused salt electrolysisB. Self reductionC. Aqueous solution electrolysisD. Thermite reduction . |
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Answer» Correct Answer - A Ag and Au do not react with `CuSO_4` + `H_(2)SO_4` solution. |
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| 270. |
In the commercial electrochemical process for aluminium extraction, the electrolyte used isA. `Al(OH)_3` in NaOH solutionB. An aqueous solution of `Al_2(SO_4)_3`C. A molten mixture of `Al_(2)O_3` and `Na_(3)AlF_6`D. A motlen mixture of `Al_(2)O_3 ` and `Al(OH)_3` |
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Answer» Correct Answer - C Lead is mainly extracted from galena (PbS). The metallic sulphides like `Cu_(2)S`, PbS, HgS, `Sb_(2)S_(3)` etc., when heated strongly in free supply of air and `SiO_2` (roasting ) get reduced directly to free metal .This is called auto reduction or self reduction. `2PbS + 3O_2` `rarr` 2PbO + `2SO_4` , 2PbO + PbS `rarr` 3Pb + `SO_2` Tin is generally from tin stone. Metal is obtained by carbon reduction process. `SnO_(2) + 2C overset(Delta)toSn+2COuarr` |
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| 271. |
Among the following statements the incoorect one isA. Calamine and siderte are oxidesB. Argentite and cuprite are oxidesC. Zinc blende and iron pyrites are sulphides.D. Malachite and azurite are ores of copper. |
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Answer» Correct Answer - B Magnesium is extracted by the electrolysis on fused salt `(MgCl_2)` |
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| 272. |
Coke can be used to reduce `Cu_(2)O`. Explain it based on thermodynamic view. |
| Answer» The graph of `C to CO` remains below the graph of `Cu to Cu_(2)O` after about `120^(@)C` when carbon can act as reducing agent. | |
| 273. |
Write some uses of aluminimum. |
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Answer» `(i)` In making silver paint `(ii)` In making utensils `(iii)` In making alloys for parts of aeroplane `(iv)` As reducing agent in the extraction of `Cr` from `Cr_(2)O_(3)`, `Mn` from `Mn_(2)O_(3)`, `MO` from `Mo_(2)O_(3)`, etc |
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| 274. |
Roasting is carried out in case of:A. GalenaB. Iron pyritesC. Copper glanceD. All. |
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Answer» Correct Answer - D All sulphides are roasted. |
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| 275. |
Giving examples differentiate between roasting and calcination. |
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Answer» `(i)` The end product of both the processes is oxide of metal. `(ii)` Volatile impurities are removed from the ore and surface area for the further reaction increases. |
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| 276. |
Which of the following statements, about the advantage of roasting of sulphide ore before reduction is not trueA. Roasting of the sulphide to the oxide is thermodynamics feasibleB. Carbon and hydrogen are suitable reducing agents for metal sulphidesC. The `delta(fG)^(o0)` of the sulphide is greater than those for `CS_2` and `H_(2)S`D. The `delta(fG)^(o)` is negative for roasting of sulphide ore to oxide. |
| Answer» Correct Answer - B | |
| 277. |
A sulphide ore `(A)` on roasting leaves a residue `(B)`. `(B)` on heating with chlorine gives `(C )`, sulphide in water, addition of excess potassium iodide to a solution of `(C )` gives a solution `(D)` A brown precipitate `(E)` is formed when a solution of ammonium sulphate is added to an alkaline a solution of `(D)`. Identify `(A)` to `(E)`. |
| Answer» `underset((A))(HgS)overset("Roasting")(to)underset((B))(HgO)overset(Cl_(2))(to)underset((C))(HgCl_(2))overset("Excess of Kl")(to)underset((D))(K_(2)Hgl_(4))underset((NH_(4))_(2)SO_(4))overset("Alkaline")(to)underset("Brown ppt"(E))(HgO.Hg(NH_(2))l)` | |
| 278. |
Sulphide ores are common for the metalsA. Ag , Cu and PbB. Ag , Cu and SnC. Ag , Mg and PbD. Al , Cu and Pb |
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Answer» Correct Answer - C Sulphide ore are common for Ag (silver glance : `Ag_(2)S` , Cu (copper pyrites : `CuFeS_2` and Pb (galena, Pbs ) . |
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| 279. |
Which of the following statement is incorrect regarding the metallurgy of aluminium by electrolystic method ?A. Electrolyte is `Al_(2)O_(3)` dissolved in `Na_(2)AlF_(3)` containing a little of `CaF_(2)`B. Bauxite ore is purified before carrying out the electrolysisC. Aluminium being heavier than electrolyte floats over the surface of the latterD. Anode consist of a number of graphite rods which are periodically replaced |
| Answer» Correct Answer - C | |
| 280. |
Native silver metal forms a water soluble complex with a dilute solution of NaCN in the presence ofA. nitrogenB. oxygenC. carbon dioxideD. argon |
| Answer» Correct Answer - B | |
| 281. |
Corondum is ……………mineral of Al.A. silicateB. oxideC. double saltD. sulphate. |
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Answer» Correct Answer - (B) |
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| 282. |
Discharge potential relates to the potential at whichA. the metal is discharged at the anodeB. the metal is discharged at the cathodeC. the metal ion is dischargedD. the metal is reduced |
| Answer» Correct Answer - B | |
| 283. |
A naturally occurring substance from which a metal can be profitably extracted is known asA. MineralB. GangueC. OreD. Flux |
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Answer» Correct Answer - C Ore is a naturally occuring substance from which metal can be extracted economically. |
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| 284. |
A naturally occurring substance from which a metal can be profitably extracted is known asA. OreB. SlagC. GangueD. Mineral |
| Answer» Correct Answer - D | |
| 285. |
Assertion : Tin is refined by liquation method. Reason : Tin has low melting point as compared to impurities .A. If both assertion and reason are true and reason is the correct explanation of assertion .B. if both assertion and reason are true but reason is not the correct explanation of assertionC. If assertion is true but reason is falseD. If both assertion and reason are false. |
| Answer» Correct Answer - A | |
| 286. |
In the metallurgical processes, aluminium acts asA. an oxidising agentB. a reducing agentC. a flusD. a solder. |
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Answer» Correct Answer - B Froth floatation may be used to increase the concentration of chalcopyrites. |
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| 287. |
An ore after levigation is found to have acidic impurities. Which of the following can be used as flux during smelting operation.A. `H_(2)SO_4`B. `CaCO_3`C. `SiO_2`D. Both `CaCO_3` and `SiO_2` |
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Answer» Correct Answer - (B) |
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| 288. |
In the metallurgical processes the flux used for removing acidic impurities isA. SilicaB. Sodium chlorideC. Lime stoneD. Sodium carbonate |
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Answer» Correct Answer - (C ) |
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| 289. |
Which of the following flux is used to remove acidic impurities in metallurgical processes ?A. SilicaB. Lime stoneC. Sodium chlorideD. Sodium carbonate. |
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Answer» Correct Answer - B Lime stone is used to remove acidic impurities in metallurgical processes. |
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| 290. |
In metallurgical processes the flux used for removing acidic impurities isA. LimestoneB. Sodium carbonateC. SilicaD. Common salt |
| Answer» Correct Answer - A | |
| 291. |
Oil used as frothing agent in froth-floatation process isA. coconut oilB. cartor oilC. plamitic oilD. pine oil. |
| Answer» Correct Answer - D | |
| 292. |
The reason for floating of ore particles in concentration by froth floatation is thatA. they are lightB. they are insolubleC. they are chargedD. they are hydrophobic. |
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Answer» Correct Answer - (D) |
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| 293. |
Gold and silve are extracted from their respective ores byA. LeachingB. SmeltingC. RoastingD. Hydro metallurgy. |
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Answer» Correct Answer - D Hydro metallurgy involves both leaching and precipitation of the metal from its solution by a precipitating agent. |
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| 294. |
Which process of purification is represented by the following equation `underset("Impure")Ti+2I_(2) overset(250^(@)C)to Til_(4)overset(1400^(@)C)to underset("pure")Ti+2I_(2)`A. CupellationB. PolingC. Van ArkelD. Zone refining |
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Answer» Correct Answer - C The equation is of Van - Arkel method. |
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| 295. |
Name the metal M which is extracted based on the following equationA. CuB. AuC. HfD. Hg |
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Answer» Correct Answer - B `2K[Au(CN)_2]^(-)` + Zn `rarr` `K_(2){Zn(CN)_4]` + 2Au. |
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| 296. |
The most electropositive metals are isolated from their ores byA. High temperture reduction with carbonB. Self reductionC. Thermal decompositionD. Electrolysis of fused ionic salts |
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Answer» Correct Answer - D The most electropositive metals are isolated from their ores by electrolysis of fused ionic salts. |
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| 297. |
Most electropositive metal are obtained from their ores byA. autoreductionB. smelting with carbonC. electrolysis of fused saltsD. thermal decomposition |
| Answer» Correct Answer - C | |
| 298. |
Which of the following is used as a method purification for silicon ?A. Electrolytic refiningB. LiquationC. Zone refiningD. Distillation |
| Answer» Correct Answer - C | |
| 299. |
Purification of silicon element used in semiconductors is done byA. Zone refiningB. HeatingC. Froth floatationD. Heating in vacuum . |
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Answer» Correct Answer - A Purification of Si used in semi-conductors is done by zone refining. |
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| 300. |
Galvanishing of iron sheets is done byA. Cu platingB. Zn platingC. As platingD. Tin plating |
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Answer» Correct Answer - B Galvinisation of iron sheets is done by zinc plating. |
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