InterviewSolution
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InterviewSolution
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A mineral(X) concentratedby froth floatation process was roasted in a reverberatory furance go give two compojnd (A) and (B) whichwere later partially oxidizes, B was more easily oxidised than A) to give compounds (C ) and (D) respectively. The roasted ore was mixed with silica and some powdered coke and later smalted when two layers of moltenmass was obtained-the upper layer was that of salg (E) while the lower layer is called matte (F). The molten mattel was then transferred to a bessemer converter and a blastof hot air and sand waspassed through it when the metal (Y) was obtained.Identify the mineral (X), the meta (Y) and the compounds (A-F) |
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Answer» Solution :(i) Sincemineral (X) is concentratedby frothfloatationprocess, it mustbeasulphidemineral (ii) Sinceduringroasting, the mineral(X) formedtwo compounds(A) and(B),therefore, the mineral consistsoftwo METALS, maybe , Cu andFe. If thisobservationiscorrect,thenthemineralconsists fo twometals, may be , Cu andFe.Ifthis observationis correct, thenthemineral(X) iscopperpyrites. `underset ("Copper pyriter (X)")( 2CU Fe S_2)+O_ 2overset (Delta ) tounderset("(A)") (Cu_2S )+underset("(B)") (2FeS) +SO_ 2` Since Fe ismorereactivethen Cu,therefore , FeS(B) ispreferentiallyoxidisedto FEO then`Cu_ 2S`isoxidisedto` Cu _ 2O`. Ifat allany` Cu_ 2O` isformed, itcombineswithFeS to form` Cu_ 2 S`. Duringsmelting, FeOcombineswith ` SiO_ 2`to formferroussilicateslage (E). `FeO +SiO_ 2tounderset ("FERROUS silicate (E)") ( FeSiO_3) ` The matte (F) mainlyconsistsofamixtureof`Cu_ 2 S `withsomeunchangesFeS. Duringbessemerization,FeS isoxidised to FeOwhichcombineswith `SiO_2`toform` FeSiO_ 3`slag ` Fe O+SiO_ 2toFe SiO_ 3(slag )` Some of` Cu_ 2 S`isfirstoxidized to`Cu_ 2 O`which thenreactswithremaining` Cu_ 2 S`to formcoppermetal(Y). `2Cu_ 2S+3 O_ 2to2 Cu_ 2O+2SO_ 2,2Cu_ 2O+Cu_ 2Stounderset("Copper metal (E)") ( 6 Cu) +SO _ 2` Thus,`X = Cu FeS_ 2`(copperpyrites ),Y = Cu, A =` Cu_ 2S`,B =FeS,C =` Cu_2 O`,D = FeO ,E =` FeSi O _ 3`. |
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