Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
-
- reddish brown deposit/pink deposit/mass increases
- As anode released Copper ions the concentration of copper ions does not decrease
- The anode should be made up of Nickel and the electrolyte should be aq. Nickel sulphate or any salt solution of Nickel
- \[\ce{Ag -> Ag+ + e-}\]
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.
Copy and complete the following table:
| Anode | Electrolyte | |
| Purification of copper |
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.
The following question relate to the electroplating of an article with silver.
What should be the nature of the anode?
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.
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).
Which solution is preferred as electrolyte, CuSO4 or FeSO4?
Write two applications of electrolysis in which the anode diminishes in mass.
What ions must be present in a solution used for electroplating a particular metal?
