Advertisements
Advertisements
Questions
Explain: Zone refining
Outline the principles of refining of metals by the following methods
Zone refining
Solution
Zone refining: This method is based on the principle that impurities are more soluble in the molten state of metal (the melt) than in the solid state. In the process of zone refining, a circular mobile heater is fixed at one end of a rod of impure metal. As the heater moves, the molten zone of the rod also moves with it. As a result, pure metal crystallizes out of the melt and the impurities pass onto the adjacent molten zone. This process is repeated several times, which leads to the segregation of impurities at one end of the rod. Then, the end with the impurities is cut off. Silicon, boron, gallium, indium etc. can be purified by this process.
APPEARS IN
RELATED QUESTIONS
Name the method used for the refining of Nickel metal.
Name the method of refining of metals such as Germanium.
Explain the principle of the method of electrolytic refining of metals. Give one example.
Name the common elements present in the anode mud in electrolytic refining of copper. Why are they so present ?
Outline the principles behind the refining of metals by the following methods:
Zone refining method
What happens when NaCN is added in an ore containing PbS and ZnS during concentration by froth floatation method?
Name the method of refining which is Used to obtain low boiling metal.
Electrolytic refining is used to purify which of the following metals?
In which of the following method of purification, metal is converted to its volatile compound which is decomposed to give pure metal?
(i) Heating with stream of carbon monoxide.
(ii) Heating with iodine.
(iii) Liquation.
(iv) Distillation.
Write two basic requirements for refining of a metal by Mond process and by Van Arkel Method.
Assertion: Hydrometallurgy involves dissolving the ore in a suitable reagent followed by precipitation by a more electropositive metal.
Reason: Copper is extracted by hydrometallurgy.
Electrolytic reduction method is used for the extraction of ______.
Describe a method for refining nickel.
Describe a method for refining nickel.
Describe a method for refining nickel.
Describe a method for refining nickel.
Describe a method for refining nickel.
