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Question
State one relevant observation for the following:
At the anode when aqueous copper sulphate solution is electrolysed using copper electrodes.
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Solution 1
Copper anode itself ionizes to give Cu2+ ions.
\[\ce{Cu - 2e- -> Cu^{2+}}\]
Solution 2
The anode slowly dissolves, but the colour of copper sulphate does not change. The copper anode ionises, producing Cu2+ ions that enter the CuSO4 solution. It accepts electrons to form Cu2+.
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Copy and complete the following table :
| Anode | Electrolyte | |
| Purification of copper |
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 \[\ce{Cu^2+(aq) + 2e- ->Cu(s)}\]
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- A diagram of the apparatus used for step 1 is shown
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- Write down the reaction taking place at the positive electrode during step 3.
