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Minerals from which metals can be extracted economically and easily are called ores.The extraction of metals from theirs ores involves the following processes. (i)Concentration. (ii)Calcination | roasting | leaching . (iii)Reduction. It is carried out be one of the following methods. Silver is extracted from its native ore by :A. Formation of soluble complex by dilute solution of NaCN in presence of air followed by the reduction with zincB. Formation of soluble complex by dilute solution of NaCN in absence of air followed by the reduction with zincC. Roasting followed by the self reductionD. Roasting followed by electrolytic reduction |
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Answer» Correct Answer - A `O_2` oxidases silver to silver (I) ion which then prouduce soluble complex with `CN^(-)` ions . `2Ag+4NaCN+1/2 O_2 +H_2O hArr 2Na[Ag (CN)_2]+2NaOH`. `2Na[Ag (CN)_2]+ZntoNa_2[Zn(CN)_4]+ZntoNa_2[Zn(CN)_4]+Agdarr` |
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