Questions and Answers
What is the main difference between haematite and magnetite?
Haematite is more easily reduced than magnetite
What is the purpose of sintering the ore into lumps?
To prepare the ore for use in the blast furnace
What is the role of limestone in the blast furnace?
It reacts with silica and alumina to form slag
What is the purpose of ore dressing operations?
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How can sulphur and phosphorus be removed from the iron?
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What is the maximum allowable amount of sulphur and phosphorus in steel?
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What is the primary benefit of preheating in steel production?
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What happens to the slag layer in the steel production process?
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Which reaction occurs during the production of cast iron?
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What is the primary source of aluminium for commercial extraction?
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Where does most of the sulphur end up during steel production?
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What is the function of preheating in steel production?
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What is the primary purpose of the ore dressing stage in aluminum extraction?
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What is the chemical reaction that occurs during the chemical treatment of bauxite?
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What is the primary component of bauxite?
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What is the role of cryolite in aluminum extraction?
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What happens when cryolite is immersed in water?
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Which stage of aluminum extraction involves the electrolytic process?
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What is the primary purpose of the flotation process in gold extraction?
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In the cyanidation leaching process, what is the role of zinc dust?
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Why is deaeration of the gold cyanide solution necessary before adding zinc at cold temperatures?
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Which of the following impurities can cause issues during cyanidation by consuming cyanide and oxygen unnecessarily?
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How is the effect of iron sulfides, which can form problematic iron cyanide complexes, reduced during cyanidation?
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What is the purpose of adding excess cyanide during the cyanidation process when copper is present?
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What is the primary purpose of the concentration step in copper extraction?
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What is the purpose of the roasting step in copper extraction?
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Which of the following is true about the copper ore used in commercial extraction?
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Which step in the copper extraction process is used to convert copper sulfides to copper oxides?
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What is the approximate copper content (in percentage) after the smelting and matte conversion step?
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Which step in the copper extraction process is used to achieve a copper purity of 99.9%?
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