A) boiling impure gold with dil. \[{{H}_{2}}S{{O}_{4}}\]
B) boiling impure gold with cone. \[{{H}_{2}}S{{O}_{4}}\]
C) electrolytically
D) Both [b] and [c]
Correct Answer: D
Solution :
Impurities of Cu and Ag from gold are removed by boiling impure gold with cone.\[{{H}_{2}}S{{O}_{4}}\]and also by electrolytic method. \[Cu+2{{H}_{2}}S{{O}_{4}}\xrightarrow[{}]{heat}CuS{{O}_{4}}+S{{O}_{2}}+2{{H}_{2}}O\] \[2Ag+2{{H}_{2}}S{{O}_{4}}\xrightarrow[{}]{heat}A{{g}_{2}}S{{O}_{4}}+S{{O}_{2}}+2{{H}_{2}}O\] This method is called parting. Cone.\[HN{{O}_{3}}\]can also be used for this purpose.You need to login to perform this action.
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