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Column $-\,I$ |
Column $-\,II$ |
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$(A)$ Metal which occur in the native state in nature is |
$(P)$ $Hg$ |
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$(B)$ The oxides of metal that can be commercially reduced by Aluminorthermic reduction process is |
$(Q)$ $Ti$ |
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$(C)$ van Arkel method is used for preparing ultrapure metal of |
$(R)$ $Cr$ |
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$(D)$ Auto reduction process is employed for the sulphide ore of |
$(S)$ $Ag$ |
$A-S, \,B-R, \,C-Q, \,D-P$
$A-R,\, B-S,\, C-Q, \,D-P$
$A-P, \,B-S,\, C-Q, \,D-R$
$A-Q,\,B-R, \,C-S, \,D-P$
Solution
$A.$ Silver occurs in the native state (or free state) in nature. It also occurs in the form of compounds.
$B.$ From the four elements, chromium oxides can be commercially reduced by Aluminothermic reduction process.
$C.$ Van-arkel method is very useful for preparing ultra-pure metals by removing all oxygen and nitrogen present in form of impurity in certain metals like $Zr$ and $Ti$.
$D.$ The sulphide ores of less electropositive metals like $Hg , Pb, Cu$, etc., are heated in air as to convert part of the ore into oxide or sulphate which then reacts with the remaining sulphide ore to give the metal and sulphur dioxide. No external reducing agent is used in this process. Hence called self reduction or auto reduction process.
