Chemistry ยท 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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Reducing by carbon
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Electrolysis of their molten chlorides or oxides
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Heating its sulphide ore in air
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a & b both
B
Correct answer
Explanation
Highly reactive metals have a strong affinity for oxygen and cannot be reduced by carbon; therefore, they are extracted by the electrolysis of their molten salts.
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Anode
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Cathode
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a & b both
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None of these.
B
Correct answer
Explanation
During electrolysis, positive metal ions are attracted to the negatively charged electrode, which is the cathode, where they gain electrons to become neutral metal atoms.
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Molten Chlorides
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Molten Sulphide
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Molten oxide
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None of these
A
Correct answer
Explanation
Highly reactive metals like potassium, sodium, and calcium are extracted from their molten chlorides via electrolysis because they are too reactive to be reduced by carbon.
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Molten Chlorides
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Molten Sulphide
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Molten oxide
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None of these
C
Correct answer
Explanation
Aluminium is extracted from its ore, bauxite, which is primarily aluminium oxide, through the Hall-Heroult process involving electrolysis of molten oxide.
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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 an ore strongly in the absence of air to convert carbonates into metal oxides. Roasting, by contrast, involves heating in the presence of excess air.
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Aluminium Powder
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Carbon
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Iron
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All of the above
A
Correct answer
Explanation
Manganese and chromium oxides are reduced to their respective metals using aluminium powder as a strong reducing agent; this is a thermite-type reaction.
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Endothermic reaction
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Exothermic reaction
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No reaction takes place
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All of the above
B
Correct answer
Explanation
The reduction of metal oxides by aluminium is highly exothermic, meaning it releases a significant amount of heat, often enough to keep the metal in a molten state.
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Nuclear reaction
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Redox reaction
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Thermite reaction
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None of these
C
Correct answer
Explanation
The reduction of metal oxides using aluminium powder as a reducing agent is specifically referred to as the thermite reaction.
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Calcination
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Roasting
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Electrolysis
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None of these
B
Correct answer
Explanation
Roasting is the process of heating a sulfide ore in the presence of excess air to convert it into a metal oxide.
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Galvanisation
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Crystallisation
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amalgamating
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Neutralisation
A
Correct answer
Explanation
Zinc is used for the process of Galvanisation.
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Zinc
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Copper
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Aluminium
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Silver
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Increase the size and shape
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To make water resistance
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Make it more stronger
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Make it corrosion free and scratch resistance
D
Correct answer
Explanation
electroplating is done to prevent corrosion.
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Steel pot has more friction
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Earthen pot has less friction
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Earthen pot has more friction
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Steel pot is comparatively heavier
C
Correct answer
Explanation
Earthen pot is easier to hold as it has more friction, hence, does not slips from hands easily.
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Zinc
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Sodium
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Potassium
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Copper
D
Correct answer
Explanation
Iron is reactive than Copper