Today we will discuss activity 14.7 class 8 science chapter 14 chemical effects of electric current. You should also go through activity 14.6 of chapter 14. In this activity 14.7, we will discuss the Chemical effect of electricity - Electroplating.
Activity
· We
will need copper sulphate and two copper plates of size around 10 cm × 4 cm.
· Take
250 mL of distilled water in a clean and dry beaker.
· Dissolve
two teaspoonfuls of copper sulphate in it.
· Add
a few drops of dilute sulphuric acid to the copper sulphate solution to make it
more conducting.
· Clean
copper plates with sandpaper.
· Now rinse them with water and dry them.
· Connect
the copper plates to the terminals of a battery and immerse them in copper sulphate
solution.
· Allow
the current to pass for about 15 minutes.
· Now
remove the electrodes from the solution and look at them carefully.
· Do
you find any difference in any one of them?
· Do
you find a coating over it?
· What
colour is the coating?
· Note
down the terminal of the battery with which this electrode is connected.
Observation and explanation
We place two copper electrodes in the
copper sulphate solution and pass an electric current.
Copper sulphate dissociates into copper
(Cu+2) and sulphate ions(SO4-2).
Copper ions start depositing on the
electrode connected to the negative terminal (Cathode), so a brown layer of
copper is formed on the cathode.
At
the same time, copper ions get released from the copper electrode connected to the positive terminal of the battery(anode) into the solution. So the amount of copper
ions in the solution remains constant. That’s why the process continues.
The process of depositing a layer of
any metal on another material by electricity is called electroplating.
This is the application of the chemical
effects of electric current.
Conclusion
This activity shows the process of
electroplating which is the chemical effect of electricity.
Related Topics
1. Activity14.5
2. Activity14.6
.webp)
No comments:
Post a Comment