Which of the following combinations would require an electrolytic cell?
coat aluminum onto iron
coat iron onto lead
coat copper onto tin
coat calcium onto iron
Please help.
Look at the activity series of metals. From most reactive to least it is as follows:
Ca, Al, Fe, Sn, Pb, Cu
http://www.files.chem.vt.edu/RVGS/ACT/notes/activity_series.html
Any METAL will displace the ION of a metal below it. For example,
Al + FeCl2 ==> AlCl3 + Fe (not balanced). Therefore, Fe plates out on Al spontaneously. You don't want that. You want Al to plate on Fe; that requires energy to do it and it requires an electrolytic cell.
Fe is above Pb; therefore, Fe will go in and Pb will come out which means Pb will plate onto Fe. Again, that isn't what you want; what you want will require an electrolytic cell also. Just go through the list.
I'm confused. I need help on this too. So in order for something to need an electroylytic cell, the one that plates onto the other has to be above the one it plates onto? Am I understanding this correctly?
To determine which of the given combinations would require an electrolytic cell, we need to understand the electroplating process. Electroplating is the process of depositing a layer of metal onto the surface of another metal object through an electrolytic cell.
In an electrolytic cell, an external source of electrical energy is used to drive a non-spontaneous redox reaction. The metal to be deposited (the cathode) is connected to the negative terminal of the external power source, while the metal to be coated (the anode) is connected to the positive terminal. The transfer of metal ions occurs through the electrolyte, which is a solution containing metal ions.
Now, let's analyze each combination:
1. Coat aluminum onto iron:
This combination does not require an electrolytic cell. Aluminum can be coated onto iron using a process called hot-dip coating or by using a chemical reaction.
2. Coat iron onto lead:
This combination does not require an electrolytic cell either. Iron can be coated onto lead using other methods such as hot-dip coating or by using specialized adhesives.
3. Coat copper onto tin:
This combination does require an electrolytic cell. Copper can be electroplated onto tin using an electrolytic cell, where copper would be designated as the anode and tin as the cathode.
4. Coat calcium onto iron:
This combination also does not require an electrolytic cell. Calcium cannot be directly coated onto iron through electroplating as it is not an electroplatable metal.
Therefore, the combination that would require an electrolytic cell is "coat copper onto tin."