NCERT Solutions Science for Class 8 Chapter 14 CHEMICAL EFFECTS OF ELECTRIC CURRENT | Class8 Science Chapter 14

NCERT Solutions Science for Class 8 Chapter 14 CHEMICAL EFFECTS OF ELECTRIC CURRENT available free in eteacherg.com। Here We learn class8 science Chapter 14 question answer concept of Microbe Friends and Enemies and and solve questions. NCERT Solutions Science for Class 8 Chapter 14 CHEMICAL EFFECTS OF ELECTRIC CURRENT. NCERT science Chapter 14 class 8 are part of NCERT class 8 science solution. Here we have given class8 science Chapter 14.

NCERT Solutions Science for Class 8 Chapter 14 CHEMICAL EFFECTS OF ELECTRIC CURRENT। Below these solutions consist of answers to all the important questions in NCERT book class 8th science Chapter 14. Here we solve Ncert class 8 science Chapter 14 question answer concepts all questions with easy method with expert solutions. It help students in their study, home work and preparing for exam. Soon we provide

NCERT class8 science Chapter 14 question and answers. is provided here according to the latest NCERT (CBSE) guidelines. Students can easily access which include important Chapters and deep explanations provided by our expert. Get CBSE in free PDF here. ncert solutions for class 8th science book pdf also available Click Here or you can download official NCERT website. You can also See NCERT Solutions for class 8 science book pdf with answers all Chapter to Click Here.

NCERT Solutions Science for Class 8 Chapter 14 CHEMICAL EFFECTS OF ELECTRIC CURRENT

class8 science Chapter 14

NCERT Solutions Science for Class 8 Chapter 14 CHEMICAL EFFECTS OF ELECTRIC CURRENT

science for class 8 Chapter 14 question answer

1. Fill in the blanks.

  (a) Most liquids that conduct electricity are solutions of ______________, ______________ and ______________.
  (b) The passage of an electric current through a solution causes ______________ effects.
  (c) If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the ______________ terminal of the battery.
  (d) The process of depositing a layer of any desired metal on another material by means of electricity is called ______________.

Answer : 

  (a) Most liquids that conduct electricity are solutions of acid, base and salt.
  (b) The passage of an electric current through a solution causes chemical effects.
  (c) If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the minus terminal of the battery.
  (d) The process of depositing a layer of any desired metal on another material by means of electricity is called electroplating.

2. When the free ends of a tester are dipped into a solution, the magnetic needle shows deflection. Can you explain the reason?
Answer : Deflection in the magnetic needle indicates that the circuit is complete and current has started flowing in it. That is, the solution in which both ends are immersed is a conductor of electricity.

3. Name three liquids, which when tested in the manner shown in Fig.14.9, may cause the magnetic needle to deflect.
NCERT Solutions Science for Class 8 Chapter 14 CHEMICAL EFFECTS OF ELECTRIC CURRENT


Answer : 
(i) Lemonade
(ii) spout water
(iii) Copper Sulphate

4. The bulb does not glow in the setup shown in Fig.14.10. List the possible reasons. Explain your answer.
NCERT Solutions Science for Class 8 Chapter 14 CHEMICAL EFFECTS OF ELECTRIC CURRENT

Answer : The reasons for not glowing the bulb in the picture can be the following –
(i) Fusing of bulb
(ii) weakening of the current flowing through it
(iii) non-completion of electric circuit
(iv) loosening of the wiring
(v) The solution used does not allow electric current to flow through

5. A tester is used to check the conduction of electricity through two liquids, labelled A and B. It is found that the bulb of the tester glows brightly for liquid A while it glows very dimly for liquid B. You would conclude that

  (i) liquid A is a better conductor than liquid B.
  (ii) liquid B is a better conductor than liquid A.
  (iii) both liquids are equally conducting.
  (iv) conducting properties of liquid cannot be compared in this manner.

Answer : (i) liquid A is a better conductor than liquid B.

6. Does pure water conduct electricity? If not, what can we do to make it conducting?
Answer : Pure water does not conduct electricity. To make pure water a conductor of electricity, some amount of salt is added to it.

7. In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area. Explain why they do this.
Answer : At the time of fire, firemen shut off the main power supply to the area before using the water pipes because water is a good conductor of electricity and being a good conductor of electricity, it completes the electrical circuit and conducts electricity. can shock. So it is done as a precaution.

8. A child staying in a coastal region tests the drinking water and also the seawater with his tester. He finds that the compass needle deflects more in the case of seawater. Can you explain the reason?
Answer : Since sea water has salt content, the magnetic needle for sea water shows more deflection, whereas drinking water has less salt content. Water mixed with salt is a good conductor of electricity, so it happens.

9. Is it safe for the electrician to carry out electrical repairs outdoors during heavy downpour? Explain.
Answer : It is absolutely unsafe for a lineman to repair the outer main line during heavy rains. It can also be dangerous, as water is a good conductor of electricity and the presence of water when wet in heavy rain will clog the electrical circuit and increase the risk of electrocution.

10. Paheli had heard that rainwater is as good as distilled water. So she collected some rainwater in a clean glass tumbler and tested it using a tester. To her surprise she found that the compass needle showed deflection. What could be the reasons?
Answer : Rain water is as pure as distilled water, but rain water has salt content, so the magnetic needle shows deflection when used in rain water.

11. Prepare a list of objects around you that are electroplated.
Answer : Following are the list of electro coated items-
(i) Bright parts of cars, buses, trucks, motorcycles.
(ii) Gold polished jewellery.
(iii) Zinc coating on iron used in construction work.
(iv) Shine on the utensils of food.

12. The process that you saw in Activity 14.7 is used for purification of copper. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. Copper from impure rod is sought to be transfered to the thin copper plate. Which electrode should be attached to the positive terminal of the battery and why?
Answer : In the above experiment, pure copper rod is connected with positive charge, because negative charge is connected to impure copper rod due to which electroplating occurs on the rod with negative charge.

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