Question

The purest Zinc is made by:
A.Electrolytic refining
B.Zone refining
C.The van Arkel method
D.The Mond process

Answer 1

The process which extract metal with very high purity will be the process for Zinc to extract with purest form. The impurities of zinc are more soluble in molten state than that of solid state.

Complete step by step answer:
There are so many processes to purify metals, among them some efficient processes are,
Electrolytic refining: In this process the impure metal and pure metal are taken as anode and cathode respectively. A salt of that particular metal is taken as electrolyte. When electricity is passed the impure metals get oxidized and converted into ions. On the other hand, metal ions from the solution get reduced at cathode. By this way metal get purified and the impurities get separated and get collected under anode electrode. By this process copper (Cu) metal gets purified.
Zone refining: when the solubility of the impurities is greater in molten state than in solid state of the metal, this process is used. In this process an impure metal rod is heated by a moving heater from one end to another. When one end of the metal melts the impurities get soluble and concentrated into that particular melted area, and when the heater moves forward it leaves pure solidified metal behind. By this way all impurities get collected into one end of the metal rod. By this process Zinc (Zn) metal gets purified.
Van Arkel method: this method is also called Vapour Phase refining. In this process a volatile impure metal is heated. As a result, the metal gets vaporised and impurities left behind as solid. By this process titanium (Ti) metal gets purified from iodine.
The Mond process: in this process the impure metal reacts with CO and forms gaseous metal carbonyl. The impurities are left unreacted.by this process nickel (Ni) metal gets purified.

So, the correct answer is B.

Note:
The formula of copper sulfate is $CuS{O_4}$ . This inorganic compound can be made by an electrolysis process. In this process sulfuric acid is used in solution and copper as electrodes. Impure copper is used as anode and pure copper is used as cathode. In this process copper from anode gets oxidized and comes to the solution. The copper ions from the solution get reduced in cathode and formed metallic pure copper.