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In terms of Ellingham diagram state why ...

In terms of Ellingham diagram state why `Al_2O_3` cannot be reduced by chromium.

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Aluminium oxide cannot be reduced by chromium because `DeltaG` for the formation of `Al_2O_3` is less than that of chromium.
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ICSE-GENERAL PRINCIPLES AND PROCESSES OF ISOLATION OF ELEMENTS -EXERCISE (PART-II ( DESCRIPTIVE QUESTIONS )) (VERY SHORT ANSWER QUESTIONS)
  1. Why sulfide ores are usually concentrated by froth floatation process ...

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  2. What is Ellingham diagram?

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  3. In terms of Ellingham diagram state why Al2O3 cannot be reduced by chr...

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  4. Which reducing agent is used to reduce the oxides of less electroposit...

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  5. Which kind of ores undergo self reduction ?

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  6. What are refractory materials?

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  7. Why is MgO used for lining the inner surface of the furnace?

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  8. Indicate the temperature at which carbon can be used as a reducing age...

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  9. How would you purify a metal like Copper?

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  10. Name the purification method which involves vapour phase extraction.

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  11. Ultra pure silicon is needed by electronic industry. By which method o...

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  12. Name the three main varieties of iron. Which out of them is the purest...

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  13. What is the percentage of carbon in steel?

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  14. A crude metal is heated with iodine to form metal tetraiodide which is...

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  15. What is the principle of chromatographic separation ?

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  16. Name the most important ore of aluminium.

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  17. When bauxite ore contains considerable amount of silica as an impurity...

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  18. Name two alloys of aluminium and give their composition.

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  19. What is the composition of ignition mixture used in aluminothermy?

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  20. Which process is used to convert pure alumina into aluminium.

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