question_answer 1)
Refractory materials are generally used in furnaces because [MNR 1980; MP PMT 1986]
A)
They possess great structural strength done
clear
B)
They can withstand high temperature done
clear
C)
They are chemically inert done
clear
D)
They do not require replacement done
clear
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question_answer 2)
Main function of roasting is [MP PET/PMT 1988]
A)
To remove volatile substances done
clear
B)
Oxidation done
clear
C)
Reduction done
clear
D)
Slag formation done
clear
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question_answer 3)
Roasting is generally done in case of the following [MP PMT 1985]
A)
Oxide ores done
clear
B)
Silicate ores done
clear
C)
Sulphide ores done
clear
D)
Carbonate ores done
clear
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question_answer 4)
Heating of pyrites in air for oxidation of sulphur is called [CPMT 1973, 75, 78, 79, 94; DPMT 1982, 84, 86; MP PMT 2000, 01, 02]
A)
Roasting done
clear
B)
Calcination done
clear
C)
Smelting done
clear
D)
Slagging done
clear
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question_answer 5)
Which is not basic flux [CPMT 1986]
A)
\[CaC{{O}_{3}}\] done
clear
B)
Lime done
clear
C)
\[Si{{O}_{2}}\] done
clear
D)
\[CaO\] done
clear
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question_answer 6)
A substance which reacts with gangue to form fusible material is called [MP PMT 1990; Kurukshetra CEE 1998]
A)
Flux done
clear
B)
Catalyst done
clear
C)
Ore done
clear
D)
Slag done
clear
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question_answer 7)
When lime stone is heated strongly, it gives off \[C{{O}_{2}}\]. In metallurgy this process is known as [MP PET/PMT 1988]
A)
Calcination done
clear
B)
Roasting done
clear
C)
Smelting done
clear
D)
Ore dressing done
clear
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question_answer 8)
Electric furnaces are lined with magnesia because
A)
It is not affected by acids done
clear
B)
It gives oxygen on heating done
clear
C)
It melts at very high temperature done
clear
D)
It has no effect of electricity done
clear
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question_answer 9)
Purpose of smelting of an ore is [MP PMT 1990, 2001; Kurukshetra CEE 1998; RPMT 2000]
A)
To oxidise it done
clear
B)
To reduce it done
clear
C)
To remove vaporisable impurities done
clear
D)
To obtain an alloy done
clear
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question_answer 10)
Smelting is done in [DPMT 1979]
A)
Blast furnace done
clear
B)
Muffle furnace done
clear
C)
Open-hearth furnace done
clear
D)
Electric furnace done
clear
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question_answer 11)
In order to bring initial chemical change in the ore, the process of heating of ore below its melting point is known as
A)
Reduction done
clear
B)
Smelting done
clear
C)
Calcination done
clear
D)
Roasting done
clear
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question_answer 12)
Matte contains mainly [KCET 2000]
A)
\[C{{u}_{2}}S\]and \[FeS\] done
clear
B)
\[CuS\]and \[F{{e}_{2}}{{S}_{3}}\] done
clear
C)
\[Fe\] done
clear
D)
\[C{{u}_{2}}S\] done
clear
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question_answer 13)
The substance which is mixed with the ore for removal of impurities is termed as [MP PMT 1985, 87, 90; CPMT 1996; JIPMER 2002]
A)
Slag done
clear
B)
Gangue done
clear
C)
Flux done
clear
D)
Catalyst done
clear
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question_answer 14)
The cheap and having high melting point compound used in furnace is [CPMT 1975]
A)
\[PbO\] done
clear
B)
\[CaO\] done
clear
C)
\[HgO\] done
clear
D)
\[ZnO\] done
clear
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question_answer 15)
Which of the following substance can be used for drying gases [EAMCET 1978; MP PET 1999]
A)
\[CaC{{O}_{3}}\] done
clear
B)
\[N{{a}_{2}}C{{O}_{3}}\] done
clear
C)
\[NaHC{{O}_{3}}\] done
clear
D)
\[CaO\] done
clear
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question_answer 16)
Which one of the furnaces among the following can produce the highest temperature
A)
Muffle furnace done
clear
B)
Blast furnace done
clear
C)
Reverberatory furnace done
clear
D)
Electric furnace done
clear
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question_answer 17)
The process of heating the ore strongly in excess of air so that the volatile impurities are removed and the ore is changed to oxide is known as [AMU 1985; NCERT 1990]
A)
Calcination done
clear
B)
Roasting done
clear
C)
Froth floatation done
clear
D)
Leaching done
clear
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question_answer 18)
The role of calcination in metallurgical operations is [AMU 1984]
A)
To remove moisture done
clear
B)
To decompose carbonate done
clear
C)
To drive off organic matter done
clear
D)
To achieve all the above done
clear
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question_answer 19)
Calcination is the process of heating the ore [CPMT 1982]
A)
In a blast furnace done
clear
B)
In absence of air done
clear
C)
In presence of air done
clear
D)
None of these done
clear
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question_answer 20)
Smelting is termed to the process in which [MP PMT 1987]
A)
The ore is heated in the absence of air done
clear
B)
Ore is cold done
clear
C)
The ore is heated in the presence of air done
clear
D)
Ore is melted done
clear
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question_answer 21)
The metallurgical process in which a metal is obtained in a fused state is called [IIT 1978; MP PET 1997]
A)
Smelting done
clear
B)
Roasting done
clear
C)
Calcination done
clear
D)
Froth floatation done
clear
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question_answer 22)
Which of the following processes involves smelting [NCERT 1983]
A)
\[ZnC{{O}_{3}}\to ZnO+C{{O}_{2}}\] done
clear
B)
\[F{{e}_{2}}{{O}_{3}}+3C\to 2Fe+3CO\] done
clear
C)
\[2PbS+3{{O}_{2}}\to 2PbO+2S{{O}_{2}}\] done
clear
D)
\[A{{l}_{2}}{{O}_{3}}.2{{H}_{2}}O\to A{{l}_{2}}{{O}_{3}}+2{{H}_{2}}O\] done
clear
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question_answer 23)
Reverberatory furnace is employed in the metallurgical process mainly for [MP PMT 1994]
A)
Reduction of oxide ores done
clear
B)
Smelting of sulphide ores done
clear
C)
Conversion of chloride to sulphate done
clear
D)
Getting magnetic materials done
clear
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question_answer 24)
In metallurgy, flux is a substance used to convert [EAMCET 1988]
A)
Infusible impurities to fusible material done
clear
B)
Soluble impurities to insoluble impurities done
clear
C)
Fusible impurities to infusible impurities done
clear
D)
Mineral into silicate done
clear
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question_answer 25)
In the manufacture of iron lime stone added to the blast furnace, the calcium ion ends in the form of [MP PMT 1989; CPMT 1989; KCET 1993; IIT 1982; MADT Bihar 1995]
A)
Slag done
clear
B)
Gangue done
clear
C)
Calcium metal done
clear
D)
\[CaC{{O}_{3}}\] done
clear
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question_answer 26)
Flux added in the extraction of iron is
A)
Silica done
clear
B)
Felspar done
clear
C)
Limestone done
clear
D)
Flint done
clear
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question_answer 27)
The smelting of iron in the blast furnace involves all the following process except
A)
Oxidation done
clear
B)
Reduction done
clear
C)
Decomposition done
clear
D)
Sublimation done
clear
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question_answer 28)
In the manufacture of iron from haematite, the function of lime stone is as [CPMT 1988; MP PET 1991, 93, 95]
A)
A reducing agent done
clear
B)
Flux done
clear
C)
Slag done
clear
D)
Gangue done
clear
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question_answer 29)
The slag obtained during the extraction of copper from copper pyrites is composed mainly of [MNR 1993; MP PMT 1997; UPSEAT 2000, 01; IIT-JEE Screening 2001]
A)
\[CaSi{{O}_{3}}\] done
clear
B)
\[FeSi{{O}_{3}}\] done
clear
C)
\[CuSi{{O}_{3}}\] done
clear
D)
\[Si{{O}_{2}}\] done
clear
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question_answer 30)
Complex is formed in the extraction of [MP PET 1989]
A)
\[Na\] done
clear
B)
\[Cu\] done
clear
C)
\[Ag\] done
clear
D)
\[Fe\] done
clear
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question_answer 31)
Which of the following metal is extracted by amalgamation process
A)
Tin done
clear
B)
Silver done
clear
C)
Copper done
clear
D)
Zinc done
clear
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question_answer 32)
The reaction \[2ZnS+3{{O}_{2}}\to 2ZnO+2S{{O}_{2}}\] in the metallurgical process of zinc is called [MP PET 1994]
A)
Calcination done
clear
B)
Cupellation done
clear
C)
Smelting done
clear
D)
Roasting done
clear
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question_answer 33)
Calcination is used in metallurgy for removal of [AFMC 1995]
A)
Water and sulphide done
clear
B)
Water and \[C{{O}_{2}}\] done
clear
C)
\[C{{O}_{2}}\] and \[{{H}_{2}}S\] done
clear
D)
\[{{H}_{2}}O\] and \[{{H}_{2}}S\] done
clear
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question_answer 34)
Which of the following is slag [CPMT 1994]
A)
\[CaO\] done
clear
B)
\[CaS{{O}_{4}}\] done
clear
C)
\[CaSi{{O}_{3}}\] done
clear
D)
\[Si{{O}_{2}}\] done
clear
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question_answer 35)
The impurties associated with minerals used in metallurgy are collectively called [MP PMT 1995; RPMT 1999]
A)
Slag done
clear
B)
Flux done
clear
C)
Gangue done
clear
D)
Ore done
clear
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question_answer 36)
When a metal is to be extracted from its ore, if the gangue associated with the ore is silica, then [MP PET 1996]
A)
An acidic flux is needed done
clear
B)
A basic flux is needed done
clear
C)
Both acidic and basic flux are needed done
clear
D)
Neither of them is needed done
clear
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question_answer 37)
Which statement is correct
A)
Gangues are carefully chosen to combine with the slag present in the ore to produce easily fusible flux to carry away the impurities done
clear
B)
Slags are carefully chosen to combine with the flux present in the ore to produce easily fusible gangue to carry away the impurities done
clear
C)
Gangues are carefully chosen to combine with the flux present in the ore to produce easily fusible slag to carry away the impurities done
clear
D)
Fluxes are carefully chosen to combine with the gangue present in the ore to produce easily fusible slag to carry away the impurities done
clear
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question_answer 38)
Roasting of copper pyrites ores is for the following purposes
A)
To burn off sulphur, arsenic, antimony etc. as oxides and convert all the iron and copper to their oxides done
clear
B)
To burn off arsenic, antimony etc. as oxides and burn off sulphur so that enough of it remains to combine with all the copper done
clear
C)
To burn off sulphur partially to leave enough to combine with arsenic, antimony etc. and to convert all the iron and copper to oxides done
clear
D)
To melt arsenic and antimony sulphides etc. and remove them by liquation and to burn off sulphur partially to leave enough to combine with copper and iron done
clear
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question_answer 39)
In the modern blast furnaces, the charge consists of a mixture of
A)
Calcined iron oxides + lime + anthracite coal done
clear
B)
Calcined iron oxides + limestone + coke done
clear
C)
Hydrated iron oxides + dolomite + coke done
clear
D)
Iron pyrites + lime +bituminous coal done
clear
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question_answer 40)
Roasting involves
A)
Only volatilisation of volatile impurities done
clear
B)
Only volatilisation of volatile impurities and decomposition of the ore done
clear
C)
Volatilisation of volatile impurities and decomposition and oxidation of the ore done
clear
D)
Oxidation and reduction of the ore and slag formation done
clear
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question_answer 41)
Which of the following ores is subjected to roasting during metallurgical operations for getting the metal oxide
A)
Horn silver done
clear
B)
Zinc blende done
clear
C)
Malachite done
clear
D)
Limonite done
clear
View Solution play_arrow
question_answer 42)
A metal obtained directly by roasting of its sulphide ore is [Pune CET 1998]
A)
\[Cu\] done
clear
B)
\[Pb\] done
clear
C)
\[Hg\] done
clear
D)
\[Zn\] done
clear
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question_answer 43)
In blast furnace, the highest temperature is in [KCET 1998]
A)
Reduction zone done
clear
B)
Slag zone done
clear
C)
Fusion zone done
clear
D)
Combustion zone done
clear
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question_answer 44)
The process of roasting of an ore is carried out in the [BHU 1999]
A)
Absence of air done
clear
B)
Presence of air done
clear
C)
Limited supply of air done
clear
D)
None of these done
clear
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question_answer 45)
Flux is used to remove [AIIMS 1999]
A)
Acidic impurities done
clear
B)
Basic impurities done
clear
C)
All impurities from ores done
clear
D)
Both a and b done
clear
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question_answer 46)
During extraction of \[Fe\]; slag obtained is [CPMT 2000]
A)
\[FeO\] done
clear
B)
\[FeSi{{O}_{3}}\] done
clear
C)
\[MgSi{{O}_{3}}\] done
clear
D)
\[CaSi{{O}_{3}}\] done
clear
View Solution play_arrow
question_answer 47)
The final step for the extraction of copper from copper pyrite in Bessemere converter involves the reaction [CPMT 2000]
A)
\[4C{{u}_{2}}O+FeS\to 8Cu+FeS{{O}_{4}}\] done
clear
B)
\[C{{u}_{2}}S+2C{{u}_{2}}O\to 6Cu+S{{O}_{2}}\] done
clear
C)
\[2C{{u}_{2}}O+FeS\to 4Cu+Fe+S{{O}_{2}}\] done
clear
D)
\[C{{u}_{2}}S+2FeO\to 2Cu+2FeCO+S{{O}_{2}}\] done
clear
View Solution play_arrow
question_answer 48)
Flux is used to remove [KCET (Med.) 2000; PCET 2004]
A)
Silica done
clear
B)
Metal oxide done
clear
C)
All impurities from ores done
clear
D)
Silica and undesirable metal oxide done
clear
View Solution play_arrow
question_answer 49)
Roasting is done in [AFMC 2001]
A)
Blast furnace done
clear
B)
Open hearth furnace done
clear
C)
Electric furnace done
clear
D)
None of these done
clear
View Solution play_arrow
question_answer 50)
Which of the following fluxes is used to remove acidic impurities in metallurgical process [KCET (Med.) 2001]
A)
Silica done
clear
B)
Lime stone done
clear
C)
Sodium chloride done
clear
D)
Sodium carbonate done
clear
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question_answer 51)
Refractory metals are used in construction of furnaces because [CPMT 2002]
A)
They can withstand high temperature done
clear
B)
They are chemically inert done
clear
C)
Their melting point is high done
clear
D)
None of these done
clear
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question_answer 52)
\[C{{N}^{-}}\]solution used in extraction of which metal [RPMT 2002]
A)
\[Ag\] done
clear
B)
\[Ti\] done
clear
C)
\[Zn\] done
clear
D)
\[Sn\] done
clear
View Solution play_arrow
question_answer 53)
In a line kiln, to get higher yield of \[C{{O}_{2}}\], the measure that can be taken is [KCET 2003]
A)
To remove \[CaO\] done
clear
B)
To add more \[CaC{{O}_{3}}\] done
clear
C)
To maintain high temperature done
clear
D)
To pump out \[C{{O}_{2}}\] done
clear
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question_answer 54)
Which metal is used as a reducing agent in smelting [MP PET 2003]
A)
C done
clear
B)
Al done
clear
C)
Zn done
clear
D)
None of these done
clear
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question_answer 55)
Inner layer of blast furnace is made of [MP PMT 1990]
A)
Graphite bricks done
clear
B)
Silica bricks done
clear
C)
Fire- clay bricks done
clear
D)
Basic bricks done
clear
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question_answer 56)
Blast furnace is employed in the smelting of oxide ore with coke and flux in the metallurgy of
A)
Iron done
clear
B)
Copper done
clear
C)
Lead done
clear
D)
All the above done
clear
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question_answer 57)
How is limestone used in Fe extraction [Orissa JEE 2004]
A)
Oxidation of Fe ore done
clear
B)
Reduction of Fe ore done
clear
C)
Formation of slag done
clear
D)
Purification of Fe formed done
clear
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question_answer 58)
Heating mixture of \[C{{u}_{2}}O\] and \[C{{u}_{2}}S\] will give [AIEEE 2005]
A)
\[Cu+S{{O}_{2}}\] done
clear
B)
\[Cu+S{{O}_{3}}\] done
clear
C)
\[CuO+CuS\] done
clear
D)
\[C{{u}_{2}}S{{O}_{3}}\] done
clear
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question_answer 59)
Heating of ore in presence of air to remove sulphur impurities is called [AFMC 2005]
A)
Calcination done
clear
B)
Roasting done
clear
C)
Smelting done
clear
D)
None of these done
clear
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question_answer 60)
The important step in the extraction of metal from carbonate ore is
A)
Calcination done
clear
B)
Roasting done
clear
C)
Electro-reduction done
clear
D)
Cupellation done
clear
View Solution play_arrow