Advertisements
Advertisements
प्रश्न
How is impure copper purified by electrolysis ? Explain.
Advertisements
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
Name the following :
The process of coating of iron with zinc
State one relevant observation for the following:
At the anode when aqueous copper sulphate solution is electrolysed using copper electrodes.
Copy and complete the following table:
| Anode | Electrolyte | |
| Purification of copper |
Choose the correct answer from the options given below:
The electrolyte used for electroplating an article with silver is
A. Silver nitrate solution
B. Silver cyanide solution
C. Sodium argentocyanide solution
D. Nickel sulfate solution
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.
State the electrode reaction at the anode during electrolysis of:
Aqueous copper sulphate solution.
Give reason for the following:
The blue colour of aqueous copper sulphate fades when it is electrolysed using platinum electrodes.
A solution of silver nitrate is a good electrolyte but is not used for electroplating an article with silver.
Describe what happens to the iron object and the copper rod.
What ions must be present in a solution used for electroplating a particular metal?
