Tag: metallurgy

Questions Related to metallurgy

Highly electropositive metals cannot be extracted by carbon reduction process because, these:

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

metals combine with carbon to form carbides
metals do not react with carbon
metal oxides are not reduced by carbon
loss of metal is more in vaporisation

For which of the following metal, the carbon reduction cannot be used?

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

Lead
Manganese
Tungsten
Iron

Of the following reduction processes, correct processes are :

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

$Fe _{2}O _{3}$ + $C$ $\rightarrow$ $Fe$
$ZnO$ + $C$ $\rightarrow$ $Zn$
$Ca _{3}(PO _{4}) _{2}$ + $C$ $\rightarrow$ $P$
$PbO$ + $C$ $\rightarrow$ $Pb$

Metals which can be extracted by smelting process are :

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

$Pb$
$Fe$
$Zn$
$Al$

The disadvantage of carbon reduction method are :

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

high temperature needed which is expensive and requires the use of a blast furnace
many metals combine with carbon forming carbides
carbon combines with oxygen to form poisonous $CO$
carbon cannot be used with highly electropositive metals

Pyrometallurgical method used for the extraction of copper from sulphide ore:

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

is a dry method
involves concentration by leaching the sulphide ore with dil. $H _2SO _4$
involves concentration of the sulphide ore by froth flotation process
statement given in (b) is incorrect

Write chemical equations for metallurgical processes to represent the reduction of $Cu _2O$ using charcoal as a reducing agent :

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

$2Cu _2O\, +\, C\, \overset{\Delta}{\rightarrow}\, 4Cu\, +\, CO _2$
$Cu _2O\, +\, C\, \overset{\Delta}{\rightarrow}\, 2Cu\, +\, CO$
$3Cu _2O\, +\, 2C\, \overset{\Delta}{\rightarrow}\, 6Cu\, +\, CO +\, CO _2$
None of these

Chemical reactions of the hydrometallurgical extraction of copper is/are?

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

$CuO\, +\, H _2SO _4\, \rightarrow\, CuSO _4\, +\, H _2O$
$CuCO _3\, +\, H _2SO _4\, \rightarrow\, CuSO _4\, +\, H _2O\, +\, CO _2$
$Cu _2S\, +\, 2H _2SO _4\, +\, 2O _2\, \rightarrow\, 2CuSO _4\, +\, SO _2\, +\, 2H _2O$
All of these

Of the following reduction processes, correct processes are:

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

$Fe _2O _3\,+\,C\,\rightarrow\,Fe$
$ZnO\,+\,C\,\rightarrow\,Zn$
$Ca _3(PO _4) _2\,+\,C\,\rightarrow\,P$
$PbO\,+\,C\,\rightarrow\,Pb$

$AgCl$ (horn silver) is converted into $Ag$ by the pyrometallurgical method.

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

True
False

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