Chemical changes occurring in conducting liquids when electric current is passed through them is called chemical effects of electric current
Note : Chemical changes occur only in conducting liquids, and not in conducting solids
Some chemical effects can be
- Bubbles of gases may be formed on the electrode
- Deposits of metals may form on the electrode
- Changes in color of the solution may occur
Bubbles of a gas on Electrodes
If electrodes are immersed in water (H 2 O),
- Oxygen bubbles are found on positive terminal
- Hydrogen bubbles fall on Negative Terminal
Deposit of Metal on Electrodes
Suppose we take copper sulphate solution and put 2 copper rods in it
We connect one rod to negative terminal of battery and other to positive terminal
If we pass an electric current through copper sulphate solution,
Copper and sulphates disassociate(copper and sulphate are separated)
Copper gets deposited on plate connected to negative terminal of battery
From the other plate, equal amount of copper gets dissolved in water and process continues
Change of Color of Solution
Here, we attach a tester to a potato
Potato is not a solution but a fresh potato contains solution of many substances dissolved in water.
When we attach a tester to a potato,
After some time,greenish blue color is found on positive terminal
However,on the negative terminal,there was no such color
