Which of the following metals is present in the anode mud during the electrolytic refining of copper ??

A)Na

B)Al

C)Au

D)Fe

Ans.

option (C) is correct. because-

In the electrolytic refining of copper the more electropositive impurities like Fe, Zn, Ni, Co, etc. dissolve in the solution and less electropositive impurities such as Ag, Au and Pt collect below the anode in the form of anodic mud.