question_answer 1)
Which one of the following is not a sulphide ore?
A)
Magnetite done
clear
B)
Iron pyrites done
clear
C)
Copper glance done
clear
D)
Sphalerite done
clear
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question_answer 2)
Which of the following pair is incorrectly matched?
A)
Magnetite - \[F{{e}_{3}}{{O}_{4}}\] done
clear
B)
Copper glance - \[C{{u}_{2}}S\] done
clear
C)
Calamine-\[ZnC{{O}_{3}}\] done
clear
D)
Zincite - \[ZnS\] done
clear
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question_answer 3)
The impurities associated with mineral used in metallurgy are called collectively?
A)
Slag done
clear
B)
Flux done
clear
C)
Gangue done
clear
D)
Ore done
clear
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question_answer 4)
Galena is an ore of
A)
Pb done
clear
B)
Hg done
clear
C)
Zn done
clear
D)
Cu done
clear
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question_answer 5)
The process of converting hydrated alumina into anhydrous alumina is called
A)
roasting done
clear
B)
smelting done
clear
C)
dressing done
clear
D)
calcination done
clear
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question_answer 6)
Which of the following statements regarding metallurgy of iron is incorrect?
A)
Reaction \[F{{e}_{3}}{{O}_{4}}+4CO\xrightarrow{{}}3Fe+4C{{O}_{2}}\] belongs to lower temperature range (500 - 800K) of the blast furnace. done
clear
B)
Reaction \[FeO+CO\xrightarrow{{}}Fe+C{{O}_{2}}\] belongs to higher temperature range (900 -1500K) of the blast furnace. done
clear
C)
The iron obtained from blast furnace is cast iron with 3% carbon. done
clear
D)
For reduction of iron oxide to occur \[\Delta G\] of the couple of following reactions should be negative \[FeO(s)\xrightarrow{{}}Fe(s)+\frac{1}{2}{{O}_{2}}(g)\] \[C(s)+\frac{1}{2}{{O}_{2}}(g)\xrightarrow{{}}CO(g)\] done
clear
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question_answer 7)
The most electropositive metals are isolated from their ores by
A)
high temperature reduction with carbon done
clear
B)
self reduction done
clear
C)
thermal decomposition done
clear
D)
electrolysis of fused ionic salts done
clear
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question_answer 8)
Which of the following condition favours the reduction of a metal oxide to metal?
A)
\[\Delta H=+ve,T\Delta S=+ve\] at low temperature done
clear
B)
\[\Delta H=+ve,T\Delta S=-ve\] at any temperature done
clear
C)
\[\Delta H=-ve,T\Delta S=-ve\] at high temperature done
clear
D)
\[\Delta H=-ve,T\Delta S=+ve\] at any temperature done
clear
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question_answer 9)
Which of the following statements regarding electrolytic refining of copper is incorrect?
A)
In this process anode is made up of impure copper and pure copper strips are taken as cathode. done
clear
B)
Acidic or basic solution of copper sulphate is used as electrolyte done
clear
C)
Antimony, tellurium, silver and gold are some of the metals deposits as anode mud during this process done
clear
D)
Zinc can be also refined by electrolytic refining method. done
clear
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question_answer 10)
If an impurity in a metal has a greater affinity for oxygen and is more easily oxidised than the metal, then the purification of metal may be carried out by
A)
Poling done
clear
B)
Zone refining done
clear
C)
Electrolytic refining done
clear
D)
Cupellation done
clear
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question_answer 11)
van Arkel method of purification of metals involves converting the metal to a
A)
volatile stable compound done
clear
B)
volatile unstable compound done
clear
C)
non volatile stable compound done
clear
D)
None of the above done
clear
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question_answer 12)
In order to refine "blister copper" it is melted in a furnace and is stirred with green logs of wood. The purpose is
A)
to expel the dissolved gases in blister copper. done
clear
B)
to bring the impurities to surface and oxidize them. done
clear
C)
to increase the carbon content of copper. done
clear
D)
to reduce the metallic oxide impurities with hydrocarbon gases liberated from the wood. done
clear
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question_answer 13)
The value of \[{{\Delta }_{f}}G{}^\circ \] for formation of \[C{{r}_{2}}{{O}_{3}}\] is \[-540\text{ }kJmo{{l}^{-1}}\] and that of \[A{{l}_{2}}{{O}_{3}}\] is \[-827\text{ }kJ\text{ }mo{{l}^{-1}}\] What is the value of \[{{\Delta }_{f}}G{}^\circ \] for the reaction? \[\frac{4}{3}Al(s)+\frac{2}{3}C{{r}_{2}}{{O}_{3}}(s)\to \frac{2}{3}A{{l}_{2}}{{O}_{3}}(s)+\frac{4}{3}Cr(s).\]
A)
\[-574\text{ }kJ\,mo{{l}^{-1}}\] done
clear
B)
\[-287\,kJ\,mo{{l}^{-1}}\] done
clear
C)
\[+574\text{ }kJ\,mo{{l}^{-1}}\] done
clear
D)
\[+287kJ\,mo{{l}^{-1}}\] done
clear
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question_answer 14)
Which of the following statement is not correct about Ellingham diagram?
A)
\[\Delta G\] increases with an increase in temperature done
clear
B)
It consists of plots of \[{{\Delta }_{f}}G{}^\circ \] Vs T for formation of oxides done
clear
C)
A coupling reaction can be well expressed by this diagram done
clear
D)
It express the kinetics of the reduction process done
clear
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question_answer 15)
Iron is obtained on large scale from \[F{{e}_{2}}{{O}_{3}}\] by
A)
Reduction with CO done
clear
B)
Reduction with Al done
clear
C)
Calcination done
clear
D)
Passing \[{{H}_{2}}\] done
clear
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question_answer 16)
Aluminothermic process is used for the extraction of metals, whose oxides are
A)
fusible done
clear
B)
not easily reduced by carbon done
clear
C)
not easily reduced by hydrogen done
clear
D)
strongly basic. done
clear
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question_answer 17)
When \[CuS{{O}_{4}}\] is electrolysed using platinum electrodes,
A)
copper is liberated at cathode, sulphur at anode done
clear
B)
copper is liberated at cathode, oxygen at anode done
clear
C)
sulphur is liberated at cathode; oxygen anode done
clear
D)
oxygen is liberated at cathode, copper at anode done
clear
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question_answer 18)
Which one of the following is a mineral of iron?
A)
Malachite done
clear
B)
Cassiterite done
clear
C)
Pyrolusite done
clear
D)
Magnetite done
clear
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question_answer 19)
In the extraction of copper from its sulphide ore, the metal finally obtained by the reduction of cuprous oxide with
A)
iron (II) sulphide done
clear
B)
carbon monoxide done
clear
C)
copper (I) sulphide done
clear
D)
sulphur dioxide done
clear
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question_answer 20)
Calamine is an ore of:
A)
zinc done
clear
B)
aluminium done
clear
C)
iron done
clear
D)
copper done
clear
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question_answer 21)
Which one of the following ores is known as Malachite:
A)
\[C{{u}_{2}}O\] done
clear
B)
\[C{{u}_{2}}S\] done
clear
C)
\[CuFe{{S}_{2}}\] done
clear
D)
\[Cu{{\left( OH \right)}_{2}}.CuC{{O}_{3}}\] done
clear
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question_answer 22)
In the isolation of metals, calcination process usually results in:
A)
metal hydroxide done
clear
B)
metal sulphide done
clear
C)
metal oxide done
clear
D)
metal carbonate done
clear
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question_answer 23)
Cryolite is
A)
\[N{{a}_{3}}Al{{F}_{6}}\] and used in the electrolysis of alumina for decreasing electrical conductivity done
clear
B)
\[N{{a}_{3}}Al{{F}_{6}}\]and used in the electrolysis of alumina for lowering the melting point of alumina done
clear
C)
\[N{{a}_{3}}Al{{F}_{6}}\]and used in the electrolytic purification of alumina done
clear
D)
\[N{{a}_{3}}Al{{F}_{6}}\] and used in the electrolysis of alumina done
clear
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question_answer 24)
Froth floatation process is used for the metallurgy of
A)
chloride ores done
clear
B)
amalgams done
clear
C)
oxide ores done
clear
D)
sulphide ores done
clear
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question_answer 25)
Which of the following metal is leached by cyanide process
A)
Ag done
clear
B)
Na done
clear
C)
Al done
clear
D)
Cu done
clear
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question_answer 26)
Which of the following statements, about the advantage of roasting of sulphide ore before reduction is not true?
A)
The \[\Delta G_{f}^{{}^\circ }\] of the sulphide is greater than those for \[C{{S}_{2}}\] and \[{{H}_{2}}s\]. done
clear
B)
The \[\Delta G_{f}^{{}^\circ }\] is negative for roasting of sulphide ore to oxide. done
clear
C)
Roasting of the sulphide to the oxide is thermodynamically feasible. done
clear
D)
Carbon and hydrogen are suitable reducing agents for reduction of metal sulphides. done
clear
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question_answer 27)
Sulphide ores of metals are usually concentrated by froth flotation process. Which one of the following sulphide ores offer an exception and is concentrated by chemical leaching?
A)
Galena done
clear
B)
Copper pyrite done
clear
C)
Sphalerite done
clear
D)
Argentite done
clear
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question_answer 28)
Pb and Sn are extracted from their chief ore by
A)
carbon reduction and self reduction. done
clear
B)
self reduction and carbon reduction. done
clear
C)
electrolysis and self reduction. done
clear
D)
self-reduction and electrolysis. done
clear
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question_answer 29)
Which of the following elements is present as the impurity to the maximum extent in the pig iron?
A)
Manganese done
clear
B)
Carbon done
clear
C)
Silicon done
clear
D)
Phosphorus done
clear
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question_answer 30)
Which of the following pairs of metals is purified by van Arkel method?
A)
Ga and in done
clear
B)
Zr and Ti done
clear
C)
Ag and Au done
clear
D)
Ni and Fe done
clear
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question_answer 31)
The following reactions take place in the blast furnace in the preparation of impure iron. Identify the reaction pertaining to the formation of the slag
A)
\[F{{e}_{2}}{{O}_{3}}(s)+3CO(g)\to 2Fe(l)+3C{{O}_{2}}(g)\] done
clear
B)
\[CaC{{O}_{3}}(s)\to CaO(s)+C{{O}_{2}}(g)\] done
clear
C)
\[CaO\left( s \right)+Si{{O}_{2}}\left( s \right)\to CaSi{{O}_{3}}\left( s \right)\] done
clear
D)
\[2C\left( s \right)+{{O}_{2}}\left( g \right)\to 2CO\left( g \right)\] done
clear
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question_answer 32)
Aluminium is extracted from alumina \[(A{{l}_{2}}{{O}_{3}})\] by electrolysis of a molten mixture of
A)
\[A{{l}_{2}}{{O}_{3}}+HF+NaAl{{F}_{4}}\] done
clear
B)
\[A{{l}_{2}}{{O}_{3}}+Ca{{F}_{2}}+NaAl{{F}_{4}}\] done
clear
C)
\[A{{l}_{2}}{{O}_{3}}+N{{a}_{3}}Al{{F}_{6}}+Ca{{F}_{2}}\] done
clear
D)
\[A{{l}_{2}}{{O}_{3}}+KF+N{{a}_{3}}Al{{F}_{6}}\] done
clear
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question_answer 33)
Correct match is:
A)
Bayer's method - \[N{{a}_{2}}C{{O}_{3}}\] done
clear
B)
Matte - 98% \[C{{u}_{2}}S+2\]% \[FeS\] done
clear
C)
van Arkel method - AgI done
clear
D)
Thomas slag - Raw material for cement industry done
clear
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question_answer 34)
Consider the following metallurgical processes:
(I) Heating impure metal CO and distilling the resulting volatile carbonyl \[\left( b.p.\text{ }43{}^\circ C \right)\] and finally decomposition at \[150{}^\circ -200{}^\circ C\] to get the pure metal
(II) Heating the sulphide ore in air until a part is converted to oxide and then furher heating in the absence of air to let the oxide react with unchanged metal sulphide
(III) Electrolysis of the molten electrolyte containing approximately equal amounts of the metal chloride and \[NaCl\] to obtained the metal
The processes used for obtaning magnesium, nickel and copper are respectively:
A)
(I), (II) and (III) done
clear
B)
(II), (III) and (I) done
clear
C)
(III), (I) and (II) done
clear
D)
(II), (I) and (III) done
clear
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question_answer 35)
When copper pyrites is roasted in excess of air, a mixture of \[CuO+FeO\] is formed. \[FeO\] is present as impurity. This can be removed as slag during reduction of \[FeO\]. The flux added to form slag is
A)
\[Si{{O}_{2}}\] which is an acidic flux done
clear
B)
Limestone, which is a basic flux done
clear
C)
\[Si{{O}_{2}}\] which is the basic flux done
clear
D)
CaO, which is a basic flux done
clear
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question_answer 36)
One of the processes used for concentration of ores is Froth floatation process. This process is generally used for concentration of sulphide ores. Sometimes in this process we add NaCN as a depressant. NaCN is generally added in case of ZnS and PbS minerals. What is the purpose of addition of NaCN during the process of Froth floatation?
A)
NaCN causes reduction by precipitation done
clear
B)
A soluble complex is formed by reaction between NaCN and ZnS while PbS forms froth done
clear
C)
A soluble complex is formed by reaction between NaCN and PbS while ZnS forms froth done
clear
D)
A precipitate of \[Pb{{(CN)}_{2}}\] is produced while ZnS remain unaffected. done
clear
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question_answer 37)
Which of the following statement(s) is/are correct?
(i) Cast iron is used in the manufacture of railway sleepers (ii) Wrought iron is used in the manufacture of anchors, bolts, chains etc. (iii) Nickel steel is used in making pendulums.
A)
Only (i) done
clear
B)
(i) and (ii) done
clear
C)
(i),(ii) and (iii) done
clear
D)
Only (iii) done
clear
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question_answer 38)
A coupled reaction takes place as follow-
\[A+B\xrightarrow{{}}C+D\] \[\Delta G{}^\circ =+xkj\] \[D+E\xrightarrow{{}}F\] \[\Delta G{}^\circ =-ykj\] for the spontaneity of reaction \[A+B+E\xrightarrow{{}}C+F\], which of the following is correct?
A)
\[2x=y\] done
clear
B)
\[x<y\] done
clear
C)
\[x>y\] done
clear
D)
\[x=\left( y \right)\times T\Delta S\] done
clear
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question_answer 39)
The form of iron obtained from blast furnace is:
A)
Steel done
clear
B)
Cast Iron done
clear
C)
Pig Iron done
clear
D)
Wrought Iron done
clear
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question_answer 40)
Calcination is the process in which:
A)
ore is heated above its melting point to expel \[{{H}_{2}}O\] or \[C{{O}_{2}}\] or \[S{{O}_{2}}\] done
clear
B)
ore is heated below its melting point to expel volatile impurities done
clear
C)
ore is heated above its melting point to remove S, As and Sb as \[S{{O}_{2}},\,\,A{{s}_{2}}{{O}_{3}}\] and \[S{{b}_{2}}{{O}_{3}}\] respectively done
clear
D)
ore is heated below its melting point to expel \[{{H}_{2}}O\] or \[C{{O}_{2}}\] done
clear
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question_answer 41)
In Goldschmidt aluminothermic process which of the following reducing agents is used:
A)
calcium done
clear
B)
coke done
clear
C)
Al-powder done
clear
D)
sodium done
clear
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question_answer 42)
Pyrolusite is a/an
A)
oxide ore done
clear
B)
sulphide ore done
clear
C)
carbide ore done
clear
D)
Not an ore done
clear
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question_answer 43)
Among the following statements the incorrect one is
A)
Calamine and siderite are carbonates done
clear
B)
Argentite and cuprite are oxides done
clear
C)
Zinc blende and iron pyrites are sulphides done
clear
D)
Malachite and azurite are ores of copper. done
clear
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question_answer 44)
During smelting an additional substance is added which combines with impurities to form a fusible product. It is known as
A)
slag done
clear
B)
mud done
clear
C)
gangue done
clear
D)
flux done
clear
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question_answer 45)
Which of the following processes involve the roasting process?
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 46)
Before introducing \[FeO\]in blast furnace , it is converted to \[F{{e}_{2}}{{O}_{3}}\] by roasting so that
A)
it may not be removed as slag with silica done
clear
B)
it may not evaporate in the furnace done
clear
C)
presence of it may increase the m.pt. of charge done
clear
D)
None of these done
clear
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question_answer 47)
In electrorefining of copper some gold is deposited as
A)
anode mud done
clear
B)
cathode mud done
clear
C)
electrolyte done
clear
D)
None of these done
clear
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question_answer 48)
In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with:
A)
Copper (I) sulphide \[(C{{u}_{2}}S)\] done
clear
B)
Sulphur dioxide \[\left( S{{O}_{2}} \right)\] done
clear
C)
Iron sulphide \[\left( FeS \right)\] done
clear
D)
Carbon monoxide (CO) done
clear
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question_answer 49)
\[XC{{l}_{2}}(excess)+YC{{l}_{2}}\xrightarrow{{}}XC{{l}_{4}}+Y\downarrow ;\] \[YO\xrightarrow[>400{}^\circ ]{\Delta }\frac{1}{2}{{O}_{2}}+Y,\] Ore of Y would be:
A)
Siderite done
clear
B)
Cinnabar done
clear
C)
Malachite done
clear
D)
Hornsilver done
clear
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question_answer 50)
Refractory materials are generally used in furnaces because
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 51)
In electro-refining of metal the impure metal is made the anode and a strip of pure metal, the cathode, during the electrolysis of an aqueous solution of a complex metal salt. This method cannot be used for refining of
A)
silver done
clear
B)
copper done
clear
C)
aluminium done
clear
D)
sodium done
clear
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question_answer 52)
When the sample of copper with zinc impurity is to be purified by electrolysis, the appropriate electrodes are
A)
B)
C)
D)
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question_answer 53)
In the extraction of aluminium by Hall-Heroult process, purified \[A{{l}_{2}}{{O}_{3}}\] is mixed with \[Ca{{F}_{2}}\] to
(i) lower the melting point of \[A{{l}_{2}}{{O}_{3}}\].
(ii) increase the conductivity of molten mixture.
(iii) reduce \[A{{l}^{3+}}\] into \[Al\left( s \right).\]
(iv) acts as catalyst.
A)
(i) and (ii) done
clear
B)
(i), (ii) and (iii) done
clear
C)
(iii) and (iv) done
clear
D)
(ii), (iii) and (iv) done
clear
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question_answer 54)
In Hall-Heroult process how much carbon anode is burnt away to produce each 1kg of aluminium?
A)
0.3kg done
clear
B)
0.5kg done
clear
C)
1kg done
clear
D)
0.1kg done
clear
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question_answer 55)
Which of the oxide groups among the following cannot be reduced by carbon?
A)
\[C{{u}_{2}}O,Sn{{O}_{2}}\] done
clear
B)
\[CaO,{{K}_{2}}O\] done
clear
C)
\[PbO,F{{e}_{2}}{{O}_{4}}\] done
clear
D)
\[F{{e}_{2}}{{O}_{3}},ZnO\] done
clear
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question_answer 56)
Extraction of zinc from zinc blende is achieved by
A)
roasting followed by self-reduction done
clear
B)
electrolytic reduction done
clear
C)
roasting followed by reduction with carbon done
clear
D)
roasting followed by reduction with another metal done
clear
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question_answer 57)
The substance used as froth stabilisers in froth- floatation process is
A)
Potassium ethyl xanthate done
clear
B)
Aniline done
clear
C)
Sodium cyanide done
clear
D)
Copper sulphate done
clear
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question_answer 58)
When a metal is to be extracted from its ore and the gangue associated with the ore is silica, then
A)
an acidic flux is needed done
clear
B)
a basic flux is needed done
clear
C)
both acidic and basic fluxes are needed done
clear
D)
Neither of them is needed done
clear
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question_answer 59)
Which one of the following ores is not concentrated by froth floatation process?
A)
Copper pyrites done
clear
B)
Pyrargyrite done
clear
C)
Pyrolusite done
clear
D)
Zinc blende done
clear
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question_answer 60)
Which of the following reactions is an example for calcination process?
A)
\[2Ag+2HCl+(O)\to 2AgCl+{{H}_{2}}O\] done
clear
B)
\[2Zn+{{O}_{2}}\to 2ZnO\] done
clear
C)
\[2ZnS+3{{O}_{2}}\to 2ZnO+2S{{O}_{2}}\] done
clear
D)
\[MgC{{O}_{3}}\to MgO+C{{O}_{2}}\] done
clear
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question_answer 61)
Heating of ore in the absence of air below its melting point is called
A)
leaching done
clear
B)
roasting done
clear
C)
smelting done
clear
D)
calcination done
clear
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question_answer 62)
Heating pyrites to remove sulphur is called
A)
smelting done
clear
B)
calcination done
clear
C)
liquation done
clear
D)
roasting done
clear
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question_answer 63)
Complexes formed in the following methods are
I.
Mond's process for purification of nickel.
II.
Removal of lead poisoning from the body.
III.
Cyanide process for extraction of silver.
IV.
Froth flotation process for separation of ZnS from galena ore by using depressant.
A)
B)
C)
D)
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question_answer 64)
The method of zone refining of metals is based on the principle of:
A)
Greater solubility of the impurity in the molten state than in the solid done
clear
B)
Greater mobility of the pure metal than that of the impurity done
clear
C)
Higher melting point of the impurity than that of the pure metal done
clear
D)
Greater noble character of the solid metal than that of the impurity done
clear
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question_answer 65)
\[{{\Delta }_{f}}G{{~}^{-}}vs\]T plot in the Ellingham diagram slopes downward for the reaction
A)
\[Mg+\frac{1}{2}{{O}_{2}}\to MgO~\] done
clear
B)
\[2Ag+\frac{1}{2}{{O}_{2}}\to A{{g}_{2}}O\] done
clear
C)
\[C+\frac{1}{2}{{O}_{2~}}\to CO\] done
clear
D)
\[CO+\frac{1}{2}{{O}_{2~}}\to C{{O}_{2}}\] done
clear
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question_answer 66)
Purification of silicon element used in semiconductors is done by
A)
zone refining done
clear
B)
heating done
clear
C)
froth floatation done
clear
D)
heating in vacuum done
clear
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question_answer 67)
In the electrolysis of alumina to obtain aluminiumb metal, cryolite is added mainly to
A)
lower the melting point of alumina done
clear
B)
dissolve alumina in molten cryolite done
clear
C)
remove the impurities of alumina done
clear
D)
increase the electrical conductivity done
clear
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question_answer 68)
Cassiterite is concentrated by
A)
levigation done
clear
B)
electromagnetic separation done
clear
C)
floatation done
clear
D)
liquefaction done
clear
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question_answer 69)
Calcination is used in metallurgy for removal of?
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 70)
Which of the following metals is extracted by the electrometallurgical method?
A)
Cu done
clear
B)
Fe done
clear
C)
Na done
clear
D)
Ag done
clear
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