Activity 14.6 Class 8 Science Chapter 14 Solution

Today we will discuss activity 14.6 class 8 science chapter 14 chemical effects of electric current.  You should also go through activity 14.5 of chapter 14. In this activity 14.6, we will discuss chemical changes that take place in ‘Electrolysis’.

 

Activity

  ·     Take out carbon rods carefully from two discarded cells.

  ·      Clean their metal caps with sandpaper.

  ·     Wrap copper wires around the metal caps of the carbon rods and join them to a battery.

  ·     We call these two-rod electrodes. (Instead of carbon rods, you may take two iron nails about 6 cm long.

  ·     Pour a cupful of water into a glass/plastic bowl.

  ·     Add a teaspoonful of salt or a few drops of lemon juice to water to make it more conducting.

  ·     Now immerse the electrodes in this solution.

  ·     Make sure that the metal caps of the carbon rods are outside the water.

  ·     Wait for 3-4 minutes.

  ·     Observe the electrodes carefully.

  ·     Do you notice any gas bubbles near the electrodes?

  ·     Can we call the change taking place in the solution a chemical change?

  ·     Recall the definition of a chemical change that you learned in Class VII.

      

 Activity 14.6 Class 8 Science Chapter 14 Solution

Observation and explanation

When an electric current is passed through electrodes, a chemical reaction takes place so bubbles can be seen on the electrodes.

The chemical reaction which takes place depends upon the solution and electrodes we take.

We can see the following changes –

  1. Deposition of metal on electrodes

  2. Change in colour of the solution

 

Yes, we can call these changes chemical changes

Conclusion

In this activity, we can see chemical changes during the electrolytic process.

Related Topics

1. Activity 14.7

2. Activity 14.5