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Question
Describe what happens to the iron object and the copper rod.
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Solution
The copper anode continuously dissolves as ions in solution and is replaced periodically. The electrolyte dissociates into Cu2+ ions, which migrate towards the iron object taken as the cathode and are deposited as neutral copper atoms on the cathode.
Electrolyte: Aqueous solution of nickel sulphate
Dissociation: \[\ce{CuSO4 ⇌ Cu^2^+ + SO^2^-4}\]
\[\ce{H2O ⇌ H^+ + OH^-}\]
Electrodes:
- Cathode: Article to be electroplated
- Anode: Block of pure copper
Electrode reactions:
- Reaction at cathode: \[\ce{Cu^{2+} + 2e^- -> Cu}\] (deposited)
- Reaction at anode: \[\ce{Cu - 2e^- -> Cu^{2+}}\]
RELATED QUESTIONS
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
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.
Explain the term:
Electro refining
How is impure copper purified by electrolysis ? Explain.
List out the main applications of electrolysis.
The following questions are about electroplating of copper wire with silver.
(a) What ions must be present in the electrolyte?
(b) Of what substance must the anode be made up of?
(c) What will the cathode be made up of?
(d) Write the equation for the reaction which takes place at the cathode.
Mr Ramu wants electrolyte his key chain with nickel to prevent rusting. For this electroplating
(i) Name the electrolyte
(ii) Name the cathode
(iii) Name the anode
(iv) Give the reaction at the cathode
(v) Give the reaction at the anode
