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प्रश्न
Describe what happens to the iron object and the copper rod.
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उत्तर
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: \[\ce{Cu - 2e^- -> Cu^{2+}}\]
APPEARS IN
संबंधित प्रश्न
Name the following :
The process of coating of iron with zinc
Name the metallic ions that should be present in the electrolyte when an article made of copper is to be electroplated with silver.
Give one word or phrase for the following:
Electrolytic deposition of a superior metal on a baser metal.
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.
A solution of silver nitrate is a good electrolyte but is not used for electroplating an article with silver.
Copy and complete the following table :
| Anode | Electrolyte | |
| Purification of copper |
Draw a labelled diagram to show how iron is electroplated with copper.
What ions must be present in a solution used for electroplating a particular metal?
Electroplating steel objects with silver involves a three-step process.
Step 1: A coating of copper is applied to the object.
Step 2: A coating of nickel is applied to the object.
Step 3: The coating of silver is applied to the object.
-
- A diagram of the apparatus used for step 1 is shown
- The chemical process taking place on the surface of the object is \[\ce{Cu^2+(aq) + 2e- ->Cu(s)}\]
What is the observation seen on the surface of the object? - Explain why the concentration of copper ions in the electrolyte remains constant throughout step 1.
- The chemical process taking place on the surface of the object is \[\ce{Cu^2+(aq) + 2e- ->Cu(s)}\]
- A diagram of the apparatus used for step 1 is shown
- Give two changes which would be needed in order to coat nickel on to the object in step 2.
- Write down the reaction taking place at the positive electrode during step 3.
