Name the method of refining of metals such as Germanium.

Out of and which one is more effective in causing coagulation of negatively charged sol and why?

Out of sulphur sol and proteins, which one forms multimolecular colloids?

In the extraction of impure is dissolved in conc. NaOH to form sodium aluminate and leaving impurities behind. What is the name of this process?

What is the role of coke in the extraction of iron from its oxides?