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प्रश्न
How is impure copper purified by electrolysis ? Explain.
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उत्तर
Electrolytic refining is used for the purification of copper. In this case
Cathode : Pure copper strip
Anode : Impure copper
Electrolyte : A solution of copper sulphate and dilute sulphuric acid.
When the current is passed through the electrolyte , the copper ions of the copper sulphate solution are attracted to the cathode where they gain electrons and are deposited on pure copper strips. The impure copper loses electrons and passes into solution as soluble copper ions.
At Cathode : Cu+2 + 2e- → Cu
At anode : Cu + 2e- → Cu+2
APPEARS IN
संबंधित प्रश्न
Identify the substance underlined, in the following case
The electrolyte used for electroplating an article with silver.
Name the following :
The process of coating of iron with zinc
An electrolytic cell is set up using two platinum electrodes and an aqueous solution of copper (II) sulphate,
(a)draw a labelled diagram of the electrolytic cell,
(b)Name the ions present in the cell,
(c)Name the ions migrating towards the anode,
(d)Name the ions migrating towards the cathode,
(e)Name the ions which will not be discharged at electrodes during electrolysis,
(f)Write the reaction at the cathode,
(g)Write the reaction at the anode,
(h)Name the spectator ion in the solution.
Give three applications of electrolysis.
Explain the term:
Electro refining
List out the main applications of electrolysis.
The following question relate to the electroplating of an article with silver.
Name the electrode formed by the article which is to be plated.
The following question relate to the electroplating of an article with silver.
What should be the nature of the anode?
Element X is a metal with valency 2. Element Y is a non-metal with valency 3.
(a) Write equations to show how X and Y form ions.
(b) If Y is diatomic gas, write the equation for the direct combination of X and Y to form a compound.
(c) Write two applications of electrolysis in which anode diminish in mass.
(d) If the compound formed between X and Y is melted and an electric current passed through the molten compound, the element X will be obtained at the _____ and the Y at the ________of the electrolytic cell. (Provide the missing words).
A solution of silver nitrate is a good electrolyte but is not used for electroplating an article with silver.
