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Metallrgical process can be explained in...

Metallrgical process can be explained in terms of thermodynamic principles. Reduction of `Cr_2O_3` by Aluminium metal is accompained by negative `DeltaG^@`value and is thermodynamically feasible. Why does this reaction fail at room temperature?

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The reactions is `Cr_2O_3+2Al rarr Al_2O_3 + 2Cr` for which `DeltaG^@` is negative. Certain amount of activation energy is required for this reaction to take place. So heating is required and it does not take place at room temperature.
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A N EXCEL PUBLICATION-GENERAL PRINCIPLES AND PROCESSES OF ISOLATION OF ELEMENTS-QUESTION BANK
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  2. What is the significance of leaching in the extraction of aluminium?

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  3. Metallrgical process can be explained in terms of thermodynamic princi...

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  4. Why is reduction of a metal oxide easier if the metal formed is in liq...

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  5. Is it ture under certain conditions Mg can reduce Al2O3 and Al can red...

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  6. Analyses the table given below: Which of the ores mentioned in the ...

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  7. Identify the ores that can be concentrated by leaching.

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  8. What do you mean by leaching?

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  9. You are provided with samples of some impure metals such as titanium a...

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  10. What is the name of the method that is used in manufacturing of sodium...

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  11. The concept of DeltaG^@ of coupled reaction are used explain reduction...

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  12. In the blast furnace for manufacturing iron, most of the reduction is ...

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  13. Bauxite, Al2O3.xH2O is an important ore of aluminium. It is concentrat...

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  14. All ores are minerals, but all minerals are not ores. Why?

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  15. Carbonate ores are usually subjected to calcination, while sulphide or...

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  16. Match the items of Column I with items of Column II

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  17. Why is reduction of a metal oxide easier if the metal formed is in liq...

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  18. The scientific and technological process used for isolation of the met...

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  19. The concept of DeltaG^@ of coupled reaction are used explain reduction...

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  20. Give two examples for alloy

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