Is it safe for the electrician to carry out electrical repairs outdoors during heavy downpour? Explain.

Important Questions on Chemical Effects of Electric Current

EASY

8th Jammu and Kashmir Board

IMPORTANT

SCIENCE TEXTBOOK FOR CLASS 8>Chapter 8 - Chemical Effects of Electric Current>Exercises>Q 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?

EASY

8th Jammu and Kashmir Board

IMPORTANT

SCIENCE TEXTBOOK FOR CLASS 8>Chapter 8 - Chemical Effects of Electric Current>Exercises>Q 11

Prepare a list of objects around you that are electroplated.

MEDIUM

8th Jammu and Kashmir Board

IMPORTANT

SCIENCE TEXTBOOK FOR CLASS 8>Chapter 8 - Chemical Effects of Electric Current>Exercises>Q 12

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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. The process that you saw in the above activity, 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 transferred to the thin copper plate. Which electrode should be attached to the positive terminal of the battery and why?