Questions and Answers
What is the purpose of roasting in the extraction of crude metals from concentrated ores?
To oxidize the concentrated ore
Why is it necessary to convert the concentrated ore into oxides before reducing it to elemental metals?
To make reduction easier
Which of the following elements is NOT removed as an impurity during roasting of sulphide ores?
Oxygen
What happens to the nonmagnetic part of the ore during the extraction process?
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In which state does the metal exist in the concentrated ore before reduction?
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Why is roasting commonly applied for converting sulphide ores into oxides?
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What is the basis for interpreting ΔG in metallurgical processes?
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Why is the reduction of oxides of active metals by carbon considered thermodynamically not feasible?
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What does a positive E0 value indicate for the electrolysis process of metal salts?
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How is the Gibbs free energy change related to the electrode potential of the redox couple?
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What technique is used for extracting active metals like sodium and potassium from their ores?
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When will a redox reaction be considered planned according to the text?
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What is the product formed when borax reacts with acids?
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What is a use of borax mentioned in the text?
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How is boric acid prepared according to the text?
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What is the color of boric acid as per the text?
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What does boric acid form when reacting with sodium hydroxide?
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What is formed when urea fuses with B(OH)3 in an ammonia atmosphere at high temperature?
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What is one advantage of using the vapour phase method for refining metals?
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What is the purpose of an inert gas atmosphere in the melt method?
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Why does impurities move along with the molten zone in the melt method?
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How are elements like germanium, silicon, and gallium refined in the melt method?
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What happens to impure nickel in the Mond process for refining nickel?
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What distinguishes the vapour phase method from the melt method in metal refining processes?
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What are the products formed when heating Potash alum to red hot?
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What is the result of treating Potash alum with ammonium hydroxide?
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What are the uses of Alum as mentioned in the text?
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Where is carbon primarily found in its native form?
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Which element occurs as silica in sand and quartz crystal?
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