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Aluminothermy used for the spot welding ...

Aluminothermy used for the spot welding of large iron sturctures is based upon the fact that

A

As compared to iron, aluminium has greater affinity for oxygen

B

As compared to aluminium, ironhas greater affinity for oxygen

C

Reaction between aluminium and oxygen is endothermic

D

Reaction between iron oxide and alumi-nium is endothermic

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A
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AAKASH SERIES-PRINCIPLES OF METALLURGY-Objective Exercise - 1 (Extration of some metals)
  1. The matter obtained in the metallurgy of copper has the approximate ...

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  2. The metal extracted by leaching with a cyanide is

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  3. The chemical reagent used for leaching of gold and silver ores is

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  4. Name the metal M, which is extracted based on the following equation ...

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  5. Of the following metals that cannot be obtained by electolysis of the ...

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  6. Commercially important ore of copper is its

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  7. Which is the chief ore of copper ?

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  8. Match the extraction processes listed in Column-I with metals listed i...

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  9. The chemical composition of slag formed during smelting process in the...

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  10. The statement that is not correct is

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  11. Chemical leaching is useful in the concen-tration of

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  12. The electrolytic reduction method for the preparation of aluminium is ...

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  13. In the electrolytic reduction of alumina, the anodic product is

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  14. Which of the following process is used in the extractive metallurgy of...

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  15. In the Bayer's process of purification of red hauxite the leaching age...

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  16. A common metal widely used in the displacement method to obtain other ...

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  17. The metal extracted by leaching with a cyanide is

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  18. Alloy used in making anchors, bolts, chains and wires

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  19. Aluminothermy used for the spot welding of large iron sturctures is ba...

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  20. Coinage alloy contains copper. The other metal present may be

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