Salt bridge
When two electrodes are in the same solution, and a potential is applied, ions flow from one electrode to the other through the solution. This forms a layer on the electrodes, leading to unstable measurements.
A salt bridge allows the current to flow through it, whilst maintaining electrical neutrality.
Salt bridges are often made of filter paper or, the more durable option, (glass) tubes.
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Electrodes used with a potentiostat
This section gives a short overview of the three types of electrodes (working, reference, counter electrode) you will encounter while using a potentiostat. It is explained how these electrodes look like and what their task is.