Please refer to Chemical Effects of Electric Current Class 8 Science Important Questions with solutions provided below. These questions and answers have been provided for Class 8 Science based on the latest syllabus and examination guidelines issued by CBSE, NCERT, and KVS. Students should learn these problem solutions as it will help them to gain more marks in examinations. We have provided Important Questions for Class 8 Science for all chapters in your book. These Board exam questions have been designed by expert teachers of Standard 8.
Class 8 Science Important Questions Chemical Effects of Electric Current
Question. (a) Does pure water conduct electricity ? If not, what can we do to make it conducting.
Answer : Pure water does not conduct electricity as it does not contain any type of salts. Adding, a small amount of Common salt (Sodium Chloride i.e. NaCl) will turn the water to a conducting medium.
(b) Is it safe for the electricians to carry out electrical repairs outdoor during heavy downpour?
Explain.
Answer : No. It is not safe to repair electrical appliances outdoors during a heavy downpour.
Rainwater is composed of a certain percentage of dissolved salts making it conductive. This may cause electric shocks and harm the electrician while working outdoors during heavy downpours.
Question. What is electroplating? Explain with the help of labeled diagram .Write any two uses of it in daily life.
Answer : Electroplating is the process of depositing a layer of a desired metal on the other metal by passing electricity.
To deposit a layer of copper metal on an iron object, take a glass jar and fill it with copper sulphate solution. Connect the plate of copper metal to the positive terminal (anode) of battery and iron object to the negative terminal (cathode) of the battery. Now, dip these two electrodes in the solution of copper sulphate. When electric current is passed through the CuSO4 solution, you will find that a thin layer of copper metal is deposited on the cathode (iron object) and an equivalent amount of copper is lost by the anode (copper plate).
Uses:
1. Electroplating is used to prevent rusting of iron articles. For this purpose a layer of zinc metal is deposited on iron articles with the help of electricity.
2. It is used to for decorative purpose and making things beautiful. For example, gold plated jewellery.