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All questions of General Principles and Processes of Isolation of Elements for JEE Exam
Copper can be extracted from (1978)- a)Kupfernical
- b)Dolomite
- c)Malachite
- d)Galena
Correct answer is option 'C'. Can you explain this answer?
Copper can be extracted from (1978)
a)
Kupfernical
b)
Dolomite
c)
Malachite
d)
Galena
|
|
Abhijeet Ingle answered |
Malachite is a green copper carbonate hydroxide mineral with a chemical composition of cu2( co3)(oh)2
it was used as an ore of copper but is of minor importance today because of presence of copper in small quantities
it was used as an ore of copper but is of minor importance today because of presence of copper in small quantities
Which method of purification is represented by the following equation ? [2012]
- a)Zone refining
- b)Cupellation
- c)Polling
- d)Van Arkel
Correct answer is option 'D'. Can you explain this answer?
Which method of purification is represented by the following equation ? [2012]
a)
Zone refining
b)
Cupellation
c)
Polling
d)
Van Arkel
|
Rohit Jain answered |
Van Arkel is a method in which heat treatment is used to purify metal in this process metals are converted into other metal compound for loosly coupled like as iodine to make metal iodide which are easily decomposed and give pure metal.
The process is known as Van Arkel method.
The process is known as Van Arkel method.
In the context of the Hall - Heroult process for the extraction of Al, which of the following statements is false ?[JEE M 2015]
- a)Al3+ is reduced at the cathode to form Al
- b)Na3AlF6 serves as the electrolyte
- c)CO and CO2 are produced in this process
- d)Al2O3 is mixed with CaF2 which lowers the melting pointof the mixture and brings conductivit 112y
Correct answer is option 'B'. Can you explain this answer?
In the context of the Hall - Heroult process for the extraction of Al, which of the following statements is false ?[JEE M 2015]
a)
Al3+ is reduced at the cathode to form Al
b)
Na3AlF6 serves as the electrolyte
c)
CO and CO2 are produced in this process
d)
Al2O3 is mixed with CaF2 which lowers the melting pointof the mixture and brings conductivit 112y
|
Devika Banerjee answered |
In the metallurgy of aluminium, purified Al2O3 is mixed with Na3AlF6 or CaF2 which lowers the melting point of the mix and brings conductivity.
Upon heating with Cu2S, the reagent(s) that give coppermetal is/are (JEE Adv. 2014)- a)CuFeS2
- b)CuO
- c)Cu2O
- d)CuSO4
Correct answer is option 'B,C,D'. Can you explain this answer?
Upon heating with Cu2S, the reagent(s) that give coppermetal is/are (JEE Adv. 2014)
a)
CuFeS2
b)
CuO
c)
Cu2O
d)
CuSO4
|
Shounak Datta answered |
Cu2S + 2Cu2O → 6Cu + SO2
Cu2S + 2CuO → 4Cu + SO2
Cu2S + CuSO4 → 3Cu + 2SO2
Cu2S + 2CuO → 4Cu + SO2
Cu2S + CuSO4 → 3Cu + 2SO2
During the process of electrolytic refining of copper, some metals present as impurity settle as ‘anode mud’. These are [2005]- a)Fe and Ni
- b)Ag and Au
- c)Pb and Zn
- d)Sn and Ag
Correct answer is option 'B'. Can you explain this answer?
During the process of electrolytic refining of copper, some metals present as impurity settle as ‘anode mud’. These are [2005]
a)
Fe and Ni
b)
Ag and Au
c)
Pb and Zn
d)
Sn and Ag
|
Kiran Mukherjee answered |
Sludge at the bottom of the refining tank. These impurities include metals such as nickel, zinc, lead, and iron.
29.5 mg of an organic compound containing nitrogen wasdigested according to Kjeldahl’s method and the evolvedammonia was absorbed in 20 mL of 0.1 M HCl solution. Theexcess of the acid required 15 mL of 0.1 M NaOH solutionfor complete neutralization. The percentage of nitrogen inthe compound is [2010]- a)59.0
- b)47.4
- c)23.7
- d)29.5
Correct answer is option 'C'. Can you explain this answer?
29.5 mg of an organic compound containing nitrogen wasdigested according to Kjeldahl’s method and the evolvedammonia was absorbed in 20 mL of 0.1 M HCl solution. Theexcess of the acid required 15 mL of 0.1 M NaOH solutionfor complete neutralization. The percentage of nitrogen inthe compound is [2010]
a)
59.0
b)
47.4
c)
23.7
d)
29.5
|
Rohan Chakraborty answered |
Answer:
23.7
Explanation:
given 29.5 milligrams of an organic compound containing nitrogen was digested according to the method and the evolved Ammonia was observed in 20 ml of 0.1 molar HCL solution the excess of the acid required 15 ml of 0.1 molar NAOH solution for complete neutralization the percentage of Nitrogen in the compound is
The percentage of N according to Kjeldahl’s method = 1.4 x N1 x V / w
N1 is normality of standard acid = 0.1 N
W is mass of organic compound = 29.5 mg = 29.5 x 10^-3 g
V is volume of N1 acid neutralised by ammonia
= (20 – 15) = 5 ml
So percentage N = 1.4 x 0.1 x 5 / 29.5 x 10^-3
= 23.7
Extraction of copper from copper pyrite (CuFeS2) involves (JEE Adv. 2016)- a)crushing followed by concentration of the ore by frothflotation
- b)removal of iron as slag
- c)self-reduction step to produce ‘blister copper’following evolution of SO2
- d)refining of ‘blister copper’ by carbon reduction
Correct answer is option 'A,B,C'. Can you explain this answer?
Extraction of copper from copper pyrite (CuFeS2) involves (JEE Adv. 2016)
a)
crushing followed by concentration of the ore by frothflotation
b)
removal of iron as slag
c)
self-reduction step to produce ‘blister copper’following evolution of SO2
d)
refining of ‘blister copper’ by carbon reduction
|
Nandita Basak answered |
CuFeS2
(A) The ore contains sulphide ions so in the purification, concentration is done by froth-floatation process.
(B) 2CuFeS2 + O2 → Cu2S + 2FeS + SO2
2FeS + 3O2 → 2FeO + 2SO2
(A) The ore contains sulphide ions so in the purification, concentration is done by froth-floatation process.
(B) 2CuFeS2 + O2 → Cu2S + 2FeS + SO2
2FeS + 3O2 → 2FeO + 2SO2
(C) 2Cu2S + 3O2 → 2Cu2O + 2SO2 (Partialoxidation)
(D) Copper is refined by electrolytic refining
In the alumino-thermite process, aluminium acts as (1983 - 1 Mark)- a)an oxidizing agent
- b)a flux
- c)a reducing agent
- d)a solder
Correct answer is option 'C'. Can you explain this answer?
In the alumino-thermite process, aluminium acts as (1983 - 1 Mark)
a)
an oxidizing agent
b)
a flux
c)
a reducing agent
d)
a solder
|
Mahi Sarkar answered |
In the alumino-thermite process, aluminium acts as a reducing agent.
The alumino-thermite process is a chemical reaction that involves the reaction between aluminium powder and a metal oxide, typically iron(III) oxide (Fe2O3). This reaction is highly exothermic, meaning it releases a large amount of heat.
Aluminium is a highly reactive metal and has a strong affinity for oxygen. In the alumino-thermite process, aluminium acts as the reducing agent, meaning it donates electrons to another substance and causes it to undergo reduction.
Here is a detailed explanation of why aluminium acts as a reducing agent in the alumino-thermite process:
1. Reducing Agents:
Reducing agents are substances that have a tendency to lose electrons and undergo oxidation. They provide electrons to another substance, which gets reduced in the process. In the alumino-thermite process, aluminium acts as the reducing agent.
2. Aluminium's Electron Configuration:
Aluminium has an atomic number of 13 and an electron configuration of 1s2 2s2 2p6 3s2 3p1. It has three valence electrons in its outermost shell, which it can readily lose to achieve a stable electron configuration.
3. Reaction with Iron(III) Oxide:
When aluminium powder reacts with iron(III) oxide, the following reaction takes place:
2Al + Fe2O3 → Al2O3 + 2Fe
In this reaction, aluminium donates three electrons to iron(III) oxide, reducing it to elemental iron. The aluminium itself is oxidized to form aluminium oxide (Al2O3).
4. Role of Aluminium:
Aluminium acts as the reducing agent in this reaction by providing electrons to iron(III) oxide. The transfer of electrons from aluminium to iron(III) oxide allows iron to be produced, which is the desired product of the alumino-thermite process.
5. Exothermic Reaction:
The alumino-thermite reaction is highly exothermic, meaning it releases a large amount of heat. This is because the reduction of iron(III) oxide by aluminium is a highly exothermic reaction. The heat released is due to the high energy released during the transfer of electrons.
In conclusion, aluminium acts as a reducing agent in the alumino-thermite process by providing electrons to the metal oxide, typically iron(III) oxide. This allows the reduction of the metal oxide and the production of elemental metal, in this case, iron.
The alumino-thermite process is a chemical reaction that involves the reaction between aluminium powder and a metal oxide, typically iron(III) oxide (Fe2O3). This reaction is highly exothermic, meaning it releases a large amount of heat.
Aluminium is a highly reactive metal and has a strong affinity for oxygen. In the alumino-thermite process, aluminium acts as the reducing agent, meaning it donates electrons to another substance and causes it to undergo reduction.
Here is a detailed explanation of why aluminium acts as a reducing agent in the alumino-thermite process:
1. Reducing Agents:
Reducing agents are substances that have a tendency to lose electrons and undergo oxidation. They provide electrons to another substance, which gets reduced in the process. In the alumino-thermite process, aluminium acts as the reducing agent.
2. Aluminium's Electron Configuration:
Aluminium has an atomic number of 13 and an electron configuration of 1s2 2s2 2p6 3s2 3p1. It has three valence electrons in its outermost shell, which it can readily lose to achieve a stable electron configuration.
3. Reaction with Iron(III) Oxide:
When aluminium powder reacts with iron(III) oxide, the following reaction takes place:
2Al + Fe2O3 → Al2O3 + 2Fe
In this reaction, aluminium donates three electrons to iron(III) oxide, reducing it to elemental iron. The aluminium itself is oxidized to form aluminium oxide (Al2O3).
4. Role of Aluminium:
Aluminium acts as the reducing agent in this reaction by providing electrons to iron(III) oxide. The transfer of electrons from aluminium to iron(III) oxide allows iron to be produced, which is the desired product of the alumino-thermite process.
5. Exothermic Reaction:
The alumino-thermite reaction is highly exothermic, meaning it releases a large amount of heat. This is because the reduction of iron(III) oxide by aluminium is a highly exothermic reaction. The heat released is due to the high energy released during the transfer of electrons.
In conclusion, aluminium acts as a reducing agent in the alumino-thermite process by providing electrons to the metal oxide, typically iron(III) oxide. This allows the reduction of the metal oxide and the production of elemental metal, in this case, iron.
Which of the following factors is of no significance forroasting sulphide ores to the oxides and not subjecting thesulphide ores to carbon reduction directly? [2008]- a)Metal sulphides are thermodynamically more stablethan CS2
- b)CO2 is thermodynamically more stable than CS2
- c)Metal sulphides are less stable than the correspondingoxides
- d)CO2 is more volatile than CS2
Correct answer is option 'C'. Can you explain this answer?
Which of the following factors is of no significance forroasting sulphide ores to the oxides and not subjecting thesulphide ores to carbon reduction directly? [2008]
a)
Metal sulphides are thermodynamically more stablethan CS2
b)
CO2 is thermodynamically more stable than CS2
c)
Metal sulphides are less stable than the correspondingoxides
d)
CO2 is more volatile than CS2
|
Avantika Saha answered |
Hence CO2 is more stable than CS2 while MS are more stable than MO.
Answer : Metal sulphide are less stable than the corresponding oxides
Of the following, the metals that cannot be obtained byelectrolysis of the aqueous solution of their salts are : (1990 - 1 Mark)- a)Ag
- b)Mg
- c)Cu
- d)Al
- e)Cr.
Correct answer is option 'B,D'. Can you explain this answer?
Of the following, the metals that cannot be obtained byelectrolysis of the aqueous solution of their salts are : (1990 - 1 Mark)
a)
Ag
b)
Mg
c)
Cu
d)
Al
e)
Cr.
|
Sahana Joshi answered |
Highly reactive metals with lower reduction potentials than hydrogen are not obtained by electrolysis of aqueous solutions of their salts since their cations cannot be reduced at cathode in presence of water. Instead of reduction of these metal cations, water undergoes reduction.
Al and Mg are reactive metals with lower reduction potentials.
Usually d-block elements are less reactive and hence can be prepared by electrolysis of their aqueous solutions.
Correct answer is option (B) Mg and (D) AI
Al and Mg are reactive metals with lower reduction potentials.
Usually d-block elements are less reactive and hence can be prepared by electrolysis of their aqueous solutions.
Correct answer is option (B) Mg and (D) AI
In the cyanide extraction process of silver from argentiteore, the oxidising and reducing agents used are (2012)- a)O2 and CO respectively
- b)O2 and Zn dust respectively
- c)HNO3 and Zn dust respectively
- d)HNO3 and CO respectively
Correct answer is option 'B'. Can you explain this answer?
In the cyanide extraction process of silver from argentiteore, the oxidising and reducing agents used are (2012)
a)
O2 and CO respectively
b)
O2 and Zn dust respectively
c)
HNO3 and Zn dust respectively
d)
HNO3 and CO respectively
|
Dipanjan Majumdar answered |
Correct answer is option: (B) O2 and Zn dust
The extraction of silver involves in cyanide process are:
Thus, in equation (i) O2 act as oxidising agent (Oxidise sulphide to SO2) and in (ii) Zn act as reducing agent (reduce Ag+ to Ag).
The extraction of silver involves in cyanide process are:
Thus, in equation (i) O2 act as oxidising agent (Oxidise sulphide to SO2) and in (ii) Zn act as reducing agent (reduce Ag+ to Ag).
Which ore contains both iron and copper? (2005S)- a)Cuprite
- b)Chalcocite
- c)Chalcopyrite
- d)Malachite
Correct answer is option 'C'. Can you explain this answer?
Which ore contains both iron and copper? (2005S)
a)
Cuprite
b)
Chalcocite
c)
Chalcopyrite
d)
Malachite
|
Pragati Dey answered |
Let's check the chemical formulae of all these ores once,
Cuprite is Cu2O, It contains, Copper and oxygen only. Chalcocite is Cu2S and it contains only copper and Sulphur, Chalcopyrite is CuFeS2, that means it contains Copper, Iron and Sulphur as well. Malchite is Cu2(CO3). That is it contains copper, carbon and oxygen. Since only chalcopyrite contains both copper and iron, it is the correct answer among the given options.
Correct answer is option: C
Cuprite is Cu2O, It contains, Copper and oxygen only. Chalcocite is Cu2S and it contains only copper and Sulphur, Chalcopyrite is CuFeS2, that means it contains Copper, Iron and Sulphur as well. Malchite is Cu2(CO3). That is it contains copper, carbon and oxygen. Since only chalcopyrite contains both copper and iron, it is the correct answer among the given options.
Correct answer is option: C
Which one of the following ores is best concentrated byfroth floatation method? [JEE M 2016]- a)Galena
- b)Malachite
- c)Magnetite
- d)Siderite
Correct answer is option 'A'. Can you explain this answer?
Which one of the following ores is best concentrated byfroth floatation method? [JEE M 2016]
a)
Galena
b)
Malachite
c)
Magnetite
d)
Siderite
|
|
Reena Dhanesh Kumar answered |
Sulphide ores are best concentrated by froth flotation.in the given options Galena(PbS) is a sulphide ore and so is the answer...
Which one of the following ores is best concentrated byfroth-flotation method ? [2004]- a)Magnetite
- b)Cassiterite
- c)Galena
- d)Malachite
Correct answer is option 'C'. Can you explain this answer?
Which one of the following ores is best concentrated byfroth-flotation method ? [2004]
a)
Magnetite
b)
Cassiterite
c)
Galena
d)
Malachite
|
Mihir Patel answered |
Galena (ZnS) is a sulphide ore. Galena is best concentrated by froth floatation method. Froth floatation method is used to concentrate sulphide ores. Magnetite (Fe3O4) is an ore of iron . Malachite (Cu2CO3(OH)2) is an ore of copper and cassiterite (SnO2) is an ore of tin. Hence, only galena contains sulphide ion.
Extraction of zinc from zinc blende is achieved by (2007)- a)electrolytic reduction
- b)roasting followed by reduction with carbon
- c)roasting followed by reduction with another metal
- d)roasting followed by self-reduction
Correct answer is option 'B'. Can you explain this answer?
Extraction of zinc from zinc blende is achieved by (2007)
a)
electrolytic reduction
b)
roasting followed by reduction with carbon
c)
roasting followed by reduction with another metal
d)
roasting followed by self-reduction
|
Roshni Chavan answered |
Answer: b) roasting followed by reduction with carbon is the correct answer.
Explanation:
Zinc has atomic number 30.
Its oxidation state is +2.
It is present in ores along with copper, silver and lead.
It is also present in Snake's venom and animal cells.
The important minerlas of Zinc are
Zinc blend
Calamine
Zincite
Willemite
The carbon reduction process consists of 4 stages
Concentration
Roasting
Reduction
Purification
In concentration zinc blend ore is freed from rocky materials.
This can be done by gravity seperation, flotation and electromagnetic seperation.
The concentrated zinc sulphide ore is roasted in reverberatory furnance in presence of excess air.
It takes place at 1000K.
Then the reduction process is fine by retort process or smelting.
Purification, the last step is done by electrolytic refining.
Hence, b) roasting followed by reduction with carbon is the correct answer.
Explanation:
Zinc has atomic number 30.
Its oxidation state is +2.
It is present in ores along with copper, silver and lead.
It is also present in Snake's venom and animal cells.
The important minerlas of Zinc are
Zinc blend
Calamine
Zincite
Willemite
The carbon reduction process consists of 4 stages
Concentration
Roasting
Reduction
Purification
In concentration zinc blend ore is freed from rocky materials.
This can be done by gravity seperation, flotation and electromagnetic seperation.
The concentrated zinc sulphide ore is roasted in reverberatory furnance in presence of excess air.
It takes place at 1000K.
Then the reduction process is fine by retort process or smelting.
Purification, the last step is done by electrolytic refining.
Hence, b) roasting followed by reduction with carbon is the correct answer.
Aluminium is extracted by the electrolysis of [2002]- a)bauxite
- b)alumina
- c)alumina mixed with molten cryolite
- d)molten cryolite.
Correct answer is option 'C'. Can you explain this answer?
Aluminium is extracted by the electrolysis of [2002]
a)
bauxite
b)
alumina
c)
alumina mixed with molten cryolite
d)
molten cryolite.
|
Krish Ghoshal answered |
Pure aluminium can be obtained by electrolysis of a mixture containing alumina, crayolite and fluorspar in the ratio 20 : 24 : 20. The fusion temperature of this mixture is 900ºC and it is a good conductor of electricity
Copper is purified by electrolytic refining of blister copper.The correct statement(s) about this process is(are) (JEE Adv. 2015)- a)Impure Cu strip is used as cathode
- b)Acidified aqueous CuSO4 is used as electrolyte
- c)Pure Cu deposits at cathode
- d)Impurities settle as anode-mud
Correct answer is option 'B,C,D'. Can you explain this answer?
Copper is purified by electrolytic refining of blister copper.The correct statement(s) about this process is(are) (JEE Adv. 2015)
a)
Impure Cu strip is used as cathode
b)
Acidified aqueous CuSO4 is used as electrolyte
c)
Pure Cu deposits at cathode
d)
Impurities settle as anode-mud
|
Swara Ahuja answered |
The correct answer is: (B, C, D)
Impure Cu is used as anode pure Cu deposited at cathode. Electrolyte is acidified solution of CuSO4. impurities settle as anode mud.
Impure Cu is used as anode pure Cu deposited at cathode. Electrolyte is acidified solution of CuSO4. impurities settle as anode mud.
The metal that cannot be obtained by electrolysis of anaqueous solution of its salts is: [JEE M 2014]- a)Ag
- b)Ca
- c)Cu
- d)Cr
Correct answer is option 'B'. Can you explain this answer?
The metal that cannot be obtained by electrolysis of anaqueous solution of its salts is: [JEE M 2014]
a)
Ag
b)
Ca
c)
Cu
d)
Cr
|
Milan Roy answered |
On electrolysis of aqueous solution of s-block elements H2 gas discharge at cathode.
Oxidation states of the metal in the minerals haematite andmagnetite, respectively, are (2011)- a)II, III in haematite and III in magnetite
- b)II, III in haematite and II in magnetite
- c)II in haematite and II, III in magnetite
- d)III in haematite and II, III in magnetite
Correct answer is option 'D'. Can you explain this answer?
Oxidation states of the metal in the minerals haematite andmagnetite, respectively, are (2011)
a)
II, III in haematite and III in magnetite
b)
II, III in haematite and II in magnetite
c)
II in haematite and II, III in magnetite
d)
III in haematite and II, III in magnetite
|
Sarthak Khanna answered |
Answer:
(d) III in haematite and II, III in magnetite is the correct answer.
Explanation:
Oxidation is loss of electrons.
The oxidation number of an atom is defined as the number of charges it will carry if electrons are completely transferred.
It is also known as oxidation state.
The oxidation state is always represented in Roman numerals.
We have to find oxidation number of minerals hematite and magnetite.
Hematite
It has formula Fe2O3.
It is a common iron oxide.
It is also known as a healing stone.
It's oxidation state is +3.
Magnetite
It has formula Fe3O4.
It is another oxide of iron.
It is naturally occurring mineral.
It is one of the components used for generation of electricity.
It has oxidation state +2 and +3.
(d) III in haematite and II, III in magnetite is the correct answer.
(d) III in haematite and II, III in magnetite is the correct answer.
Explanation:
Oxidation is loss of electrons.
The oxidation number of an atom is defined as the number of charges it will carry if electrons are completely transferred.
It is also known as oxidation state.
The oxidation state is always represented in Roman numerals.
We have to find oxidation number of minerals hematite and magnetite.
Hematite
It has formula Fe2O3.
It is a common iron oxide.
It is also known as a healing stone.
It's oxidation state is +3.
Magnetite
It has formula Fe3O4.
It is another oxide of iron.
It is naturally occurring mineral.
It is one of the components used for generation of electricity.
It has oxidation state +2 and +3.
(d) III in haematite and II, III in magnetite is the correct answer.
Which of the following process is used in the extractive metallurgy of magnesium? (2002S)- a)fused salt electrolysis
- b)self reduction
- c)aqueous solution electrolysis
- d)thermite reduction
Correct answer is option 'A'. Can you explain this answer?
Which of the following process is used in the extractive metallurgy of magnesium? (2002S)
a)
fused salt electrolysis
b)
self reduction
c)
aqueous solution electrolysis
d)
thermite reduction
|
|
Sanchita Iyer answered |
Answer:
The process of fused salt electrolysis is used in the extractive metallurgy of magnesium.
Explanation:
A fused magnesium chloride or better known as fused carnalite is used in the process of fused salt electrolysis in order to produce a resultant product of magnesium that floats on the electrolyte and also generates chlorine gas.
If normal solution electrolysis is used then it will not produce any magnesium as the water will oxidize the magnesium to magnesium oxide.
The process of fused salt electrolysis is used in the extractive metallurgy of magnesium.
Explanation:
A fused magnesium chloride or better known as fused carnalite is used in the process of fused salt electrolysis in order to produce a resultant product of magnesium that floats on the electrolyte and also generates chlorine gas.
If normal solution electrolysis is used then it will not produce any magnesium as the water will oxidize the magnesium to magnesium oxide.
Extraction of metal from the ore cassiterite involves (2011)- a)carbon reduction of an oxide ore
- b)self-reduction of a sulphide ore
- c)removal of copper impurity
- d)removal of iron impurity
Correct answer is option 'A,C,D'. Can you explain this answer?
Extraction of metal from the ore cassiterite involves (2011)
a)
carbon reduction of an oxide ore
b)
self-reduction of a sulphide ore
c)
removal of copper impurity
d)
removal of iron impurity
|
Aqsa Kibria answered |
Hiii... so cassiterite is an ore of tin
A. we usually prefer carbon reduction for Fe and Sn
B.self reduction is used only for Hg,Cuand Au
C.Sn ore consists of cu impurity so we remove that
D. Sn ore do also consists Fe impurity
Thanku
A. we usually prefer carbon reduction for Fe and Sn
B.self reduction is used only for Hg,Cuand Au
C.Sn ore consists of cu impurity so we remove that
D. Sn ore do also consists Fe impurity
Thanku
The chemical composition of ‘slag’ formed during thesmelting process in the extraction of copper is (2001S)- a)Cu2O + FeS
- b)FeSiO3
- c)CuFeS2
- d)Cu2S + FeO
Correct answer is option 'B'. Can you explain this answer?
The chemical composition of ‘slag’ formed during thesmelting process in the extraction of copper is (2001S)
a)
Cu2O + FeS
b)
FeSiO3
c)
CuFeS2
d)
Cu2S + FeO
|
Anisha Deshpande answered |
The roasting process removes volatile impurities like As or Sb from the ore. The roasted ore contains Cu2S, FeS and small quantities Cu2O, of and FeO.
The roasted ore is mixed with a little coke and sand and smelted in blast furnace.
The slag formed in the blast furnace is FeSiO3 (Ferrous silicate). The smelt formed in the blast furnace contains Cu2S and a little FeS. This mixture is called copper matte. Here, F errous oxide combines with sand to form a fusible slag. Cuprous oxide formed combines with ferrous sulphide to give ferrous oxide and cuprous sulphide.
The roasted ore is mixed with a little coke and sand and smelted in blast furnace.
The slag formed in the blast furnace is FeSiO3 (Ferrous silicate). The smelt formed in the blast furnace contains Cu2S and a little FeS. This mixture is called copper matte. Here, F errous oxide combines with sand to form a fusible slag. Cuprous oxide formed combines with ferrous sulphide to give ferrous oxide and cuprous sulphide.
Reaction:
The metal extracted by leaching with a cyanide is [2002]- a)Mg
- b)Ag
- c)Cu
- d)Na.
Correct answer is option 'B'. Can you explain this answer?
The metal extracted by leaching with a cyanide is [2002]
a)
Mg
b)
Ag
c)
Cu
d)
Na.
|
Sharmila Chavan answered |
(b) : Silver ore forms a soluble complex with NaCN from which silver is precipitated using scrap zinc.
The carbon-based reduction method is NOT used for the extraction of (JEE Adv. 2013)- a)Tin from SnO2
- b)Iron from Fe2O3
- c)Aluminium from Al2O3
- d)Magnesium from MgCO3.CaCO3
Correct answer is option 'C,D'. Can you explain this answer?
The carbon-based reduction method is NOT used for the extraction of (JEE Adv. 2013)
a)
Tin from SnO2
b)
Iron from Fe2O3
c)
Aluminium from Al2O3
d)
Magnesium from MgCO3.CaCO3
|
Janhavi Sengupta answered |
Al from Al2O3 and Mg from MgCO3.CaCO3 are separately extracted by electrolytic reduction.
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35 Years Chapter wise Previous Year Solved Papers for JEE
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