Chemistry · Science General
Metallurgical Processes
1,403 Questions
This section explores key metallurgical processes including ore concentration, pyrometallurgy, and metal refining. It also covers corrosion and the properties of refractory materials. These chemistry questions are relevant for engineering and science entrance tests.
Pyrometallurgy furnacesMetal refining techniquesCorrosion protection methodsOre concentrationAuto reduction process
Metallurgical Processes Questions
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copper sulphate
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ferromagnetic powder
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silica
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zinc suphide
B
Correct answer
Explanation
Cassette tapes use magnetic tape coated with ferromagnetic powder (such as ferric oxide or chromium dioxide). This coating allows sound to be recorded and played back through electromagnetic encoding and pickup by the tape recorder head.
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Westrosol
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PVC
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Acrylonitrile
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Oxyacetylene
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Lewisite
D
Correct answer
Explanation
This option is correct because oxyacetylene is used in welding, cutting and cleansing of iron.
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increases
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decreases
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no change
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none of these
A
Correct answer
Explanation
When iron rusts, it combines with oxygen from the air to form iron oxide (rust). Since oxygen is being added to the iron, the total weight increases. This is contrary to what many might intuitively think, as rust often appears flaky and worn away, but chemically, mass is being added to the iron.
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Roasting
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Rusting
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Rating
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None of these
B
Correct answer
Explanation
Rusting is the specific term for the corrosion of iron, where iron reacts with oxygen and moisture to form iron oxide (Fe₂O₃·nH₂O). This is a type of oxidation reaction that weakens the metal over time. Roasting is a metallurgical process, while rating is not related to corrosion.
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Calcination
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Roasting
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Electrolysis
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None of these
A
Correct answer
Explanation
Calcination is the process of heating a carbonate ore strongly in the absence of air. This converts carbonate ores like zinc carbonate (ZnCO3) into metal oxides (ZnO) and carbon dioxide. Roasting is similar but done in the presence of air, producing sulfur dioxide for sulfide ores. Electrolysis is an entirely different process using electricity.
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electroplating.
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annealing.
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galvanisation.
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vulcanisation.
C
Correct answer
Explanation
Galvanization is the process of applying a protective zinc coating to steel or iron, to prevent rusting. The most common method is hot-dip galvanizing, in which parts are submerged in a bath of molten zinc.
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nickel
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cobalt
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copper
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iron
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of decrsase in enthalpy
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of decrease in entropy
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of increase in enthalpy
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of increase in entropy
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oxygen and sulphur
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oxygen and nitrogen
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sulphur and chlorine
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Zr and Ti
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bromine
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chlorine
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carbon
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iodine
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purification of ore
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purification of metal
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reduction of metal oxide
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conversion of sulphide into oxide
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it is thermodynamically not feasible
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the temperature requirement is high
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magnesium is not a good reducing agent
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it is evident from Ellingham diagram
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cast iron
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pig iron
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wrought iron
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nickel steel
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they are inert
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they are less reactive
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they are rendered passive by oxide film
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they are difficult to oxidise
C
Correct answer
Explanation
Metals such as Cr and Al do not dissolve in concentrated nitric acid because of the formation of a passive film of oxide on the surface of metals.