3.1 Introduction to Electrolysis
- Page ID
- 32280
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Think of electrolysis and electrolytic cells as the opposite of electrochemical cells:
| Electrochemical Cells | | Electrolytic Cells | |
| | | ||
| Energy conversion | Chemical → Electrical | | Electrical → Chemical |
| Spontaneous chemical reaction? | Yes | | No |
| Value of E° | Positive | | Negative |
In an electrochemical cell, a spontaneous redox reaction is used to create an electric current; in an electrolytic cell the reverse will occur - an electric current will be required in order to cause a non-spontaneous chemical reaction to occur.
We will look at three examples of the electrolytic process, keeping our discussion on a very basic level - the electrolysis of molten sodium chloride, the electrolysis of water, and electroplating.