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

Passing current through water - teachoo.png

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

Deposit of Metal on Electrodes.png

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.

Change of Color of Solution.png

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

  1. Class 8
  2. Chapter 14 Class 8 - Chemical Effects Of Electric Current

About the Author

Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.