Advertisements
Advertisements
Question
Write the chemical equations involved in van Arkel method for refining zirconium metal.
Advertisements
Solution
This method is useful for removing impurities in the form of oxygen and nitrogen in metal like zirconium. The crude metal is heated in an evacuated vessel with iodine. The metal iodine volatilizes.
\[\ce{\underset{\text{Impure}}{Zr} + 2I2 -> \underset{\text{Vapour}}{ZrI4}}\]
The metal iodine is decomposed on tungsten filament, electrically heated to about 1800K. The pure metal is thus deposited on the filament
\[\ce{\underset{\text{Vapour}}{ZrI4} -> \underset{\text{Pure}}{Zr} + 2I2}\]
APPEARS IN
RELATED QUESTIONS
What is the principle behind the zone refining of metals?
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?
Describe a method for refining nickel.
Describe ‘froth floatation process’ for concentration of sulphide ore.
Indicate the principle behind the method used for the refining of Nickel.
Write the principle behind the following methods of refining:
Vapour-phase refining
Write down the reaction taking place in blast furnace related to the metallurgy of iron in the temperature rnge 500 K – 800 K. What is the role of limestone in the metallurgy of iron?
What happens when Silver is leached with NaCN in the presence of air?
Name the method of refining which is Used to obtain semiconductor of high purity.
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.
In the extraction of chlorine from brine:
(i) ∆GΘ for the overall reaction is negative.
(ii) ∆GΘ for the overall reaction is positive.
(iii) EΘ for overall reaction has negative value.
(iv) EΘ for overall reaction has positive value.
Write two basic requirements for refining of a metal by Mond process and by Van Arkel Method.
How are metals used as semiconductors refined? What is the principle of the method used?
Give two requirements for vapour phase refining.
Assertion: Nickel can be purified by Mond process.
Reason: \[\ce{Ni(CO)4}\] is a volatile compound which decomposes at 460 K to give pure Ni.
Assertion: Zirconium can be purificed by Van Arkel method.
Reason: ZrI4 is volatile and decomposes at 1800 K.
Assertion: Zone refining method is very useful for producing semiconductors.
Reason: Semiconductors are of high purity.
Which one of the following methods can be used to obtain highly pure metal which is liquid at room temperature?
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.
Describe a method for refining nickel.
