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Multiple choice thermodynamic principles of metallurgy general principles and processes of isolation of elements metallurgy chemistry

$Fe _3O _4$ is the chemical formula of :

  1. monazite

  2. magnetite

  3. haematite

  4. bauxite
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$Fe _3O _4$ is the chemical formula of magnetite.

Magnetite is the mineral of Iron.
Magnetite is the most magnetic of all the naturally-occurring minerals on Earth.
The chemical IUPAC name is Iron(ll,lll) oxide and the common chemical name is ferrous-ferric oxide.
So answer is B.

Multiple choice thermodynamic principles of metallurgy general principles and processes of isolation of elements metallurgy chemistry
Reduction to free metal: some of the methods commonly used to get free metal from the concentrates ore are below.
Smelting: The process of extracting a metal in the state of fusions is called smelting. In this process the ore is mixed with carbon and heated in suitable furnace
Electrolytic reduction process: This process is used in the extraction of the alkali and alkaline earth metals, zinc and aluminium.
Self reduction process: The sulphide ores of less electropositive metals like Hg, Pb, Cu etc., are heated in air so asto convert part of the ore into oxide or sulphate which then reacts with the remaining sulphide ore to give the metal.

After partial roasting, the sulphide of copper is reduced by :

  1. Reduction by carbon

  2. Electrolysis

  3. Self-reduction

  4. Cyanide process
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
In the extraction of copper, metal is formed in the Bessemer converter due to self reduction as

${ Cu } _{ 2 }S+2{ Cu } _{ 2 }O\rightarrow 6Cu+S{ O } _{ 2 }$
Multiple choice thermodynamic principles of metallurgy general principles and processes of isolation of elements metallurgy chemistry
Reduction to free metal: some of the methods commonly used to get free metal from the concentrates ore are below.
Smelting: The process of extracting a metal in the state of fusions is called smelting. In this process, the ore is mixed with carbon and heated in a suitable furnace
Electrolytic reduction process: This process is used in the extraction of the alkali and alkaline earth metals, zinc and aluminium.
Self-reduction process: The sulphide ores of less electropositive metals like Hg, Pb, Cu etc., are heated in the air so as to convert part of the ore into oxide or sulphate which then reacts with the remaining sulphide ore to give the metal.

In the metallurgical extraction of zinc from ZnO, the reducing agent used is :
  1. $CO$
  2. $SO _{2}$
  3. $CO _{2}$
  4. $NO$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
In the metallurgical extraction of zinc from ZnO, the reducing agent used is C/CO.

$ZnO + C \rightarrow   Zn + CO$
$ ZnO + CO \rightarrow  Zn + CO _2$
Multiple choice thermodynamic principles of metallurgy general principles and processes of isolation of elements metallurgy chemistry

Which of the following reaction represents the action of steam on heated iron?

  1. $3Fe+4H _2O\rightarrow Fe _3O _4+4H _2$
  2. $2Fe+3H _2O\rightarrow Fe _2O _3+3H _2$
  3. $Fe+H _2O\rightarrow FeO+H _2$
  4. $2Fe+H _2O+O _2\rightarrow Fe _2O _3+H _2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
When steam is passed over a red hot iron to form the ferric oxide and hydrogen gas is released.

The action of steam on heated iron is represented as follows:

$3Fe+4H _2O\rightarrow Fe _3O _4+4H _2$

Hence, option A is the correct answer.
Multiple choice thermodynamic principles of metallurgy general principles and processes of isolation of elements metallurgy chemistry

The smelting of iron in a blast furnace involves all the following processes except :

  1. combustion

  2. reduction

  3. slag formation

  4. sublimation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The smelting of iron in a blast furnace involves all the following processes except Sublimation.

Sublimation is the transition of a substance directly from the solid to the gas phase without passing through the intermediate liquid phase.

Multiple choice thermodynamic principles of metallurgy general principles and processes of isolation of elements metallurgy chemistry

Which of the following methods is used in the concentration of haematite ore?

  1. Hydraulic washing

  2. Magnetic separation

  3. Froth floatation process

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Haematite (Fe2O3) is an oxide ore. Magnetic separation is the most effective method for concentrating haematite because it is magnetic, allowing it to be separated from non-magnetic gangue particles.

Multiple choice thermodynamic principles of metallurgy general principles and processes of isolation of elements metallurgy chemistry

Which of the following is not an illustration of a smelting method?

  1. $2NaCl(fused)+electric \ energy\rightarrow 2Na+{Cl} _{2}$
  2. ${Al} _{2}{O} _{3}+3C \rightarrow 2Al+3CO$
  3. $2ZnS+3{O} _{2}\rightarrow 2ZnO+2{SO} _{2}$
  4. $CuO+{H} _{2}\rightarrow Cu+{H} _{2}O$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

It is the process by which a metal is obtained, either as the element or as a simple compound, from its ore by heating beyond the melting point, ordinarily in the presence of oxidizing agents, such as air, or reducing agents, such as coke. An oxidising agent is used in case of Al,Zn and Cu and so sodium reaction is not a smelting method.

Multiple choice thermodynamic principles of metallurgy general principles and processes of isolation of elements metallurgy chemistry
Reduction to free metal: some of the methods commonly used to get free metal from the concentrates ore are below.
Smelting: The process of extracting a metal in the state of fusions is called smelting. In this process, the ore is mixed with carbon and heated in a suitable furnace
Electrolytic reduction process: This process is used in the extraction of the alkali and alkaline earth metals, zinc and aluminium.
Self-reduction process: The sulphide ores of less electropositive metals like Hg, Pb, Cu etc., are heated in the air so as to convert part of the ore into oxide or sulphate which then reacts with the remaining sulphide ore to give the metal.

The metal extracted by electrolysis of its fused salt is :
  1. $Fe$
  2. $Pb$
  3. $Na$
  4. $Cu$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Na can not be obtained by electrolysis of the aqueous solution of salt as hydrogen ions have higher reduction potential than $Na^+$ so hydrogen ions will reduce first and we will get hydrogen gas instead of Na metal by electrolysis of the aqueous solution,

So sodium metal is extracted by electrolysis of its fused salt.

$NaCl \rightarrow Na^+ + Cl^-$


At cathode:
$Na^+ + e^- \rightarrow Na$