Answer 1:
Electroplating is a process of depositing a metal coating onto a metal cathode from a salt solution.
A metal cathode can be brought into a copper sulfate solution. This solution consists of Cu2+ cations and sulfate anions. When a second electrode, called the anode, is also brought in contact with the solution and a current is applied over both electrodes, charge flows through the solution. However, while the charge is being transported in the electrodes by electrons, in the solution moving ions carry the charge. The Cu2+ ions move towards the cathode and get in contact with the cathode. Now, for each Cu2+ cation two electrons move from the cathode to the ion and reduce it. The Cu2+ ions form Cu metal. The Cu metal is not soluble in the solution anymore and becomes a solid. Since this reduction reaction happens directly at the cathode, the metal solidifies on the surface of the cathode and metal plating happens. This is the process of electroplating.
Yes, this experiment can be carried out at home if you want to plate something with nickel for example.
You need:
a mason jar, an old low-voltage power supply (for example an old phone charger), white vinegar, table salt, a piece of metal that you want to plate (steel will be best), two nickel anodes (can be found on amazon.com), and two crocodile clamps.
Connect the two crocodile clamps to the positive and negative wire coming from your power supply. Fill the mason jar with white vinegar and stir some salt in. Ben your two nickel anodes so that you can hang them into the liquid in the jar with most of the anodes being in the liquid and a smaller part being outside of the jar. Make sure the two anodes won't touch each other. Now, connect the power supply with the crocodile clamps to the two nickel anodes.
Connect the positive wire to one of them and the negative to the other one. You will find out which wire is the negative one - this one will show small bubbles on the electrode. Plug in the power supply and wait for 1 to 2 hours until the solution turns light green. Now you have your nickel electrolyte. After that you start plating your piece of metal. Make sure it is clean and free of rust. Hang it into your electrolyte and connect the negative wire with the crocodile clamp to your piece of metal and the positive one to one of your nickel anodes. Turn on the power supply and start plating your piece of metal. You will see bubbles forming on your piece. This is a sign that the electroplating works. Plate it for about 20 minutes and you should see a nickel coating on your piece.
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