{"id":25930,"date":"2021-06-24T15:21:31","date_gmt":"2021-06-24T09:51:31","guid":{"rendered":"https:\/\/mcq-questions.com\/?p=25930"},"modified":"2022-03-02T10:47:36","modified_gmt":"2022-03-02T05:17:36","slug":"ncert-solutions-for-class-8-science-chapter-14","status":"publish","type":"post","link":"https:\/\/mcq-questions.com\/ncert-solutions-for-class-8-science-chapter-14\/","title":{"rendered":"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current"},"content":{"rendered":"<p>These <a href=\"https:\/\/mcq-questions.com\/ncert-solutions-for-class-8-science\/\">NCERT Solutions for Class 8 Science<\/a> Chapter 14 Chemical Effects of Electric Current Questions and Answers are prepared by our highly skilled subject experts to help students while preparing for their exams.<\/p>\n<h2>Chemical Effects of Electric Current NCERT Solutions for Class 8 Science Chapter 14<\/h2>\n<h3>Class 8 Science Chapter 14 Chemical Effects of Electric Current Textbook Exercise Questions and Answers<\/h3>\n<p><span style=\"color: #0000ff;\">Page 180-181<\/span><\/p>\n<p>Question 1.<br \/>\nFill in the blanks:<br \/>\na. Most liquids that conduct electricity are solutions of &#8230;&#8230;&#8230;&#8230;&#8230;., &#8230;&#8230;&#8230;&#8230;&#8230;. and &#8230;&#8230;&#8230;&#8230;&#8230;.<br \/>\nb. The passage of an electric current through a solution causes &#8230;&#8230;&#8230;&#8230;&#8230;. effects.<br \/>\nc. If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the &#8230;&#8230;&#8230;&#8230;&#8230;. terminal of the battery.<br \/>\nd. The process of depositing a layer of any desired metal on another material by means of electricity is called &#8230;&#8230;&#8230;&#8230;&#8230;.<br \/>\nAnswer:<br \/>\na. acids, bases and salts<br \/>\nb. chemical<br \/>\nc. negative<br \/>\nd. electroplating<\/p>\n<p>Question 2.<br \/>\nWhen the free ends of a tester are dipped into a solution, the magnetic needle shows deflection. Can you explain the reason?<br \/>\nAnswer:<br \/>\nThe deflection in the compass needle shows that current is flowing through the wound up wire and hence, through the circuit. This shows that the solution is a conducting solution because only then the current can flow through it through the circuit. This current through the wound up wire produces a magnetic field around it which acts on the magnetic needle of the compass and deflects it.<\/p>\n<p>Question 3.<br \/>\nName three liquids, which when tested in the manner shown in the figure, may cause the magnetic needle to deflect.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25931\" src=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-1.png?resize=288%2C230&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 1\" width=\"288\" height=\"230\" data-recalc-dims=\"1\" \/><br \/>\nAnswer:<br \/>\nLiquids like lemon juice, saltwater and vinegar can conduct electricity. Hence, these liquids can cause the magnetic needle to deflect.<\/p>\n<p>Question 4.<br \/>\nThe bulb does not glow in the setup shown in the figure. List the possible reasons. Explain your answer.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25933\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-2.png?resize=314%2C229&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 2\" width=\"314\" height=\"229\" srcset=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-2.png?w=314&amp;ssl=1 314w, https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-2.png?resize=300%2C219&amp;ssl=1 300w\" sizes=\"(max-width: 314px) 100vw, 314px\" data-recalc-dims=\"1\" \/><br \/>\nAnswer:<br \/>\nThe bulb may not glow because of the following reasons:<\/p>\n<ul>\n<li>Liquid in the beaker may be non-conducting. In such a case, the electric current would not be able to pass through the liquid. Hence, the circuit will not be complete.<\/li>\n<li>The conductivity of the liquid may be very low and so the current flowing through the circuit may be too weak to produce enough heat in the filament of the bulb to make it glow.<\/li>\n<li>The battery may be exhausted and may not have sufficient energy to generate electricity.<\/li>\n<li>The bulb may be fused or the circuit connections may be loose.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 5.<br \/>\nA 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<br \/>\na. liquid A is a better conductor than liquid B<br \/>\nb. liquid B is a better conductor than liquid A<br \/>\nc. both liquids are equally conducting<br \/>\nd. conducting properties of liquid cannot be compared in this manner<br \/>\nAnswer:<br \/>\na. liquid A is a better conductor than liquid B.<\/p>\n<p>Question 6.<br \/>\nDoes pure water conduct electricity? If not, what can we do to make it conducting?<br \/>\nAnswer:<br \/>\nNo, pure water does not conduct electricity. This is because pure water is devoid of any salts. Pure water can conduct electricity when a pinch of salt is added to it, as salt solution is conducting in nature.<\/p>\n<p>Question 7.<br \/>\nIn 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.<br \/>\nAnswer:<br \/>\nNormal water is a good conductor of electricity. Therefore, firemen shut off the main electrical supply for the area before using the water hoses in the case of fire to prevent themselves from getting an electric shock.<\/p>\n<p>Question 8.<br \/>\nA 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?<br \/>\nAnswer:<br \/>\nWater we use for drinking purposes has very less amount of salts dissolved in it. However, seawater has very high concentration of salts in it and hence is a greater conductor of electricity than drinking water. Therefore, more current flows through seawater and the compass needle shows more deflection in this case.<\/p>\n<p>Question 9.<br \/>\nIs it safe for the electrician to carry out electrical repairs outdoors during heavy downpour? Explain.<br \/>\nAnswer:<br \/>\nRainwater may contain many impurities which get dissolved in it when it passes through the various layers of troposphere. Due to this, rainwater becomes a good conductor of electricity. If an electrician carries out electrical repairs outdoors during heavy downpour, he may get an electric shock. Hence, it is not safe for the electrician to carry out electrical repairs outdoors during heavy downpour.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 10.<br \/>\nPaheli 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?<br \/>\nAnswer:<br \/>\nRainwater is a pure water but many impurities and acidic gases get dissolved in the rainwater while it falls to the earth through the atmosphere. Due to the presence of these impurities and small amounts of acids in it, the rainwater conducts electricity. This explains Paheli\u2019s observation that rainwater can allow electricity to pass through it while distilled water cannot.<\/p>\n<p>Question 11.<br \/>\nPrepare a list of objects around you that are electroplated.<br \/>\nAnswer:<br \/>\nExamples of electroplated objects are as follows:<\/p>\n<ul>\n<li>Chromium plating is done on different parts of cars, buses and motorcycles to give them shiny appearance.<\/li>\n<li>A fine layer of gold is deposited on the silver ornaments, and they are called gold-plated ornaments.<\/li>\n<li>Iron used in constructing a building is coated with a layer of zinc (galvanisation). This protects iron from corrosion and rusting.<\/li>\n<\/ul>\n<p>Question 12.<br \/>\nThe process that you saw in Activity 14.7 (of NCERT textbook) 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?<br \/>\nAnswer:<br \/>\nThe thin plate of pure copper should be connected to the positive terminal of the battery. This is because when electric current is passed through the copper sulphate solution, it dissociates into copper and sulphate. The free copper is drawn towards the negative terminal of the battery and gets deposited on it. On the other hand, the loss of copper from the solution would be regained from the impure copper rod which is connected to the positive terminal of the battery.<\/p>\n<p><span style=\"color: #0000ff;\">NCERT Extended Learning Activities and Projects<\/span><\/p>\n<p>Question 1.<br \/>\nTest the conduction of electricity through various fruits and vegetables. Display your result in a tabular form.<br \/>\nHint:<br \/>\nFruits such as oranges, apples, peach and grapes are good conductors of electricity whereas fruits like kiwi, banana, papaya, pineapple are poor conductors of electricity. On the other hand, vegetables such as lemon, tomatoes, carrot and reddish are good conductors of electricity whereas onion, cabbage, cauliflower are poor conductors of electricity.<\/p>\n<p>Question 2.<br \/>\nRepeat Activity 14.7 (of NCERT textbook) with a zinc plate in place of the copper plate connected to the negative terminal of the battery. Now replace zinc plate with some other metallic object and again repeat the activity. Which metal gets deposited over which other metal? Discuss your findings with your friends.<br \/>\nHint:<br \/>\nIn each case copper gets deposited over the metal plate because the electrolyte used is copper sulphate and the positive electrode is of copper.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 3.<br \/>\nFind out if there is a commercial electroplating unit in your town. What objects are electroplated there and for what purpose? (The process of electroplating in a commercial unit is much more complex than what we did in Activity 14.7). Find out how they dispose off the chemicals they discard.<br \/>\nHint:<br \/>\nDo it yourself.<\/p>\n<p>Question 4.<br \/>\nImagine that you are an \u2018entrepreneur\u2019 and have been provided a loan by a bank to set up a small electroplating unit. What object would you like to electroplate and for what purpose? (Look up the meaning of \u2018entrepreneur\u2019 in a dictionary).<br \/>\nHint:<br \/>\nIf I were an entrepreneur and was provided a loan by a bank to set up a small electroplating unit, I would start an electroplating unit of electronic and electrical appliances because:<\/p>\n<ul>\n<li>There is an increasing demand for electronic devices.<\/li>\n<li>The telecommunication industry is ever-expanding.<\/li>\n<li>Cost efficiency of electroplating these articles is high as compared to other technologies.<\/li>\n<\/ul>\n<p>Question 5.<br \/>\nFind out the health concerns associated with chromium electroplating. How are people trying to resolve them?<br \/>\nHint:<br \/>\nThe health problems associated with chromium electroplating are skin rashes, stomach ulcers, respiratory problems, weak immunity, kidney and liver damage and cancer. Steps taken to resolve it may include use of water insoluble chromium compounds and mild steel.<\/p>\n<p>Question 6.<br \/>\nYou can make a fun pen for yourself. Take a conducting metal plate and spread a moist paste of potassium iodide and starch. Connect the plate to a battery as shown in the figure. Now using the free end of the wire, write a few letters on the paste. What do you see?<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25935\" src=\"https:\/\/i2.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-3.png?resize=294%2C177&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 3\" width=\"294\" height=\"177\" data-recalc-dims=\"1\" \/><br \/>\nHint:<br \/>\nDo it yourself.<\/p>\n<p><span style=\"color: #0000ff;\">Activity 1<\/span><\/p>\n<p>Objective: To test the electrical conductivity of lemon juice (acid) or vinegar.<br \/>\nMaterials Required: A few small plastic or rubber caps of discarded bottles, lemon juice\/ vinegar, tester.<br \/>\nProcedure:<\/p>\n<ul>\n<li>Collect a few small plastic or rubber caps of discarded bottles and clean them.<\/li>\n<li>Pour one teaspoonful of lemon juice or vinegar in one cap.<\/li>\n<li>Bring your tester over this cap and let the ends of the tester dip into the lemon juice or vinegar. Take care that the ends are not more than 1 cm apart and at the same time do not touch each other. See what happens.<\/li>\n<\/ul>\n<p>Observation: On letting the ends of tester dip into the lemon juice or vinegar, the bulb starts glowing.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25936\" src=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-4.png?resize=320%2C270&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 4\" width=\"320\" height=\"270\" srcset=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-4.png?w=320&amp;ssl=1 320w, https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-4.png?resize=300%2C253&amp;ssl=1 300w\" sizes=\"(max-width: 320px) 100vw, 320px\" data-recalc-dims=\"1\" \/><br \/>\nConclusion: This activity proves that both of the lemon juice and the vinegar are good conductors of electricity.<\/p>\n<p>Liquids hich are Good Conductors: Some liquids which can conduct electricity are tap water lemon juice, vinegar, salt solution. Most of the liquids which conduct electricity are solutions of acids, bases or salts.<\/p>\n<p>Liquids which are Poor Conductors: Some liquids are bad conductors of electricity, e.g.. distilled water, honey, milk. vegetable oil, etc.<\/p>\n<p>Water: Tap water conducts electricity because it contains various salts dissolved in it. Hence, it is advised not to touch an electric switch with wet hands. Salt water also conducts electricity. However, distilled water is pure and free of salts, hence is a poor conductor.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"color: #0000ff;\">Activity 2<\/span><\/p>\n<p>Objective: To show that the distilled water is a poor conductor of electricity.<br \/>\nMaterials Required: Distilled water, plastic or rubber cap.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25937\" src=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-5.png?resize=363%2C261&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 5\" width=\"363\" height=\"261\" srcset=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-5.png?w=363&amp;ssl=1 363w, https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-5.png?resize=300%2C216&amp;ssl=1 300w\" sizes=\"(max-width: 363px) 100vw, 363px\" data-recalc-dims=\"1\" \/><\/p>\n<p>Procedure:<\/p>\n<ul>\n<li>Take about two teaspoonful of distilled water in a clean and dry plastic or rubber cap of a bottle.<\/li>\n<li>Use the tester to test whether distilled water conducts electricity or not.<\/li>\n<li>Now dissolve a pinch of common salt in distilled water and test again. Record your observations.<\/li>\n<\/ul>\n<p>Observation: The bulb of the tester does not glow when tester is put in distilled water. This means that distilled water does not conduct electricity. When tester is put in water dissolved with a pinch of salt, the bulb of the tester glows. This shows that when a pinch of salt is dissolved in distilled water, it conducts electricity.<br \/>\nConclusion: Distilled water is a poor conductor of electricity.<\/p>\n<p>Heating Effect of Electric Current:<br \/>\nThe heating effect of electric current is responsible for the glowing of the bulb. When current passes through the bulb, the filament gets heated to a high temperature and as a result the bulb starts glowing. But, if current is very small, the filament will not get heated to a high temperature and will not glow.<\/p>\n<p>Magnetic Effect of Electric Current:<br \/>\nWhen electric current passes through a conductor, a magnetic field is created around it. This is called magnetic effect of electric current. This can be demonstrated by keeping a magnetic compass near a current-carrying conductor. A magnetic compass shows deflection when it is placed near a current-carrying conductor. The deflection is the indicator of the presence of magnetic field.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25938\" src=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-6.png?resize=345%2C298&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 6\" width=\"345\" height=\"298\" srcset=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-6.png?w=345&amp;ssl=1 345w, https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-6.png?resize=300%2C259&amp;ssl=1 300w\" sizes=\"(max-width: 345px) 100vw, 345px\" data-recalc-dims=\"1\" \/><\/p>\n<p>Chemical Effects of Electric Current: A British Chemist named William Nicholson performed an experiment showing that if current is passed through water, bubbles of oxygen and hydrogen are produced. The oxygen bubbles will be present on the positive electrode and hydrogen bubbles on the negative electrode. The passage of an electric current through a conducting solution causes chemical reactions, due to which bubbles of a gas may be formed on the electrodes. Hence, it can be said that when electric current is passed through a conducting solution, some chemical reaction takes place in the solution. This is called the chemical effect of electric current. Some of the chemical effects of electric current are as follows:<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25939\" src=\"https:\/\/i2.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-7.png?resize=358%2C283&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 7\" width=\"358\" height=\"283\" srcset=\"https:\/\/i2.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-7.png?w=358&amp;ssl=1 358w, https:\/\/i2.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-7.png?resize=300%2C237&amp;ssl=1 300w\" sizes=\"(max-width: 358px) 100vw, 358px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li>Bubbles of a gas may be formed on the electrodes.<\/li>\n<li>Deposits of metal may be seen on electrodes.<\/li>\n<li>Change of colour of solution may occur.<\/li>\n<\/ul>\n<p>Potato tester: Current produces chemical effects in fruits and vegetables also. When the two ends of a tester are inserted inside a cut potato, the end connected to the positive terminal of the battery develops greenish-blue spot on the potato. This can be used to identify the positive terminal of a cell or battery concealed in a box.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25942\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-8.png?resize=379%2C244&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 8\" width=\"379\" height=\"244\" srcset=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-8.png?w=379&amp;ssl=1 379w, https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-8.png?resize=300%2C193&amp;ssl=1 300w\" sizes=\"(max-width: 379px) 100vw, 379px\" data-recalc-dims=\"1\" \/><\/p>\n<p>Electroplating: The process of depositing a layer of a desired metal on any other material by means of electricity is called electroplating. Following steps are performed in electroplating:<\/p>\n<ul>\n<li>The material which needs to be coated with the desired layer is made the negative electrode (cathode).<\/li>\n<li>The plate of desired metal is made the positive electrode (anode).<\/li>\n<li>The conducting solution is made of a salt of desired metal.<\/li>\n<li>Electric current is passed through the solution.<\/li>\n<li>The desired metal dissociates from the plate (anode) and gets deposited on the material at negative electrode (cathode).<\/li>\n<\/ul>\n<p>Electroplating of copper: During electroplating of copper, the copper plates are made the electrodes and copper sulphate solution is used. When electric current is passed through copper sulphate solution, copper sulphate dissociates into copper and sulphate. The free copper gets drawn to the negative electrode and gets deposited there. From the other electrode, an equal amount of copper gets dissolved in the solution and the process continues.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"color: #0000ff;\">Activity 3<\/span><\/p>\n<p>Objective: To show the process of electroplating.<br \/>\nMaterials Required: Two copper plates of size around 10 cm x 4 cm, copper sulphate, distilled water, beaker, dilute sulphuric acid, sandpaper and battery.<br \/>\nProcedure:<\/p>\n<ul>\n<li>Take 250 mL of distilled water in a clean and dry vessel.<\/li>\n<li>Dissolve two teaspoonful of copper sulphate in it.<\/li>\n<li>Add a few drops of dilute sulphuric acid to the copper sulphate solution to make it more conducting.<\/li>\n<li>Clean the copper plates with sand paper.<\/li>\n<li>Now rinse them with water and dry them.<\/li>\n<li>Connect the copper plates to the terminals of battery and immerse them in copper sulphate solution.<\/li>\n<li>Allow the current to pass through the circuit for about 15 minutes.<\/li>\n<li>Now remove the electrodes from the solution and observe them carefully.<\/li>\n<\/ul>\n<p>Observation: Copper metal gets deposited on the plate at negative terminal of the battery.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25943\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-9.png?resize=349%2C266&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 9\" width=\"349\" height=\"266\" srcset=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-9.png?w=349&amp;ssl=1 349w, https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-9.png?resize=300%2C229&amp;ssl=1 300w\" sizes=\"(max-width: 349px) 100vw, 349px\" data-recalc-dims=\"1\" \/><br \/>\nConclusion: When the current is passed through the copper sulphate solution, copper gets deposited on the plate acting as cathode.<\/p>\n<p>Applications of Electroplating:<br \/>\ni. Imitation jewellery is made by applying a layer of gold or silver.<br \/>\nii. Applying a layer of chromium on an article by this method is called chrome plating. Parts of bicycle, motorbike and sanitary fittings are chrome plated by this method. Chromium is shiny, and resists corrosion and scratches.<br \/>\niii. Tin cans are made by electroplating tin on iron.<br \/>\niv. Applying a natural oxide layer on an article is called anodising. Electric poles and beams on bridges are electroplated with zinc. Chrome plating and anodising help in preventing articles from corrosion.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25944\" src=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-10.png?resize=318%2C346&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 10\" width=\"318\" height=\"346\" srcset=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-10.png?w=318&amp;ssl=1 318w, https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-10.png?resize=276%2C300&amp;ssl=1 276w\" sizes=\"(max-width: 318px) 100vw, 318px\" data-recalc-dims=\"1\" \/><br \/>\nv. Galvanisation is a process in which a coating of zinc is deposited on iron to protect it from corrosion and formation of rust.<\/p>\n<p>Problem of Electroplating: The disposal of the conducting solution of electroplating factories is a major problem. It is a polluting waste, and there are specific disposal guidelines which should be followed to protect the environment.<\/p>\n<h3>Class 8 Science Chapter 14 Chemical Effects of Electric Current Additional Important Questions and Answers<\/h3>\n<p><span style=\"color: #0000ff;\">Very Short Answer Type Questions<\/span><\/p>\n<p>Question 1.<br \/>\nDefine good conductors of electricity.<br \/>\nAnswer:<br \/>\nElectric current can easily pass through some materials. Such materials are called good conductors of electricity, e.g., iron, copper, silver, aluminium, gold, etc.<\/p>\n<p>Question 2.<br \/>\nDefine bad conductors of electricity.<br \/>\nAnswer:<br \/>\nElectric current cannot pass easily through some materials. Such materials are called bad conductors of electricity, e.g., rubber, wood, asbestos, plastic, etc.<\/p>\n<p>Question 3.<br \/>\nWhy is zinc electroplated on iron?<br \/>\nAnswer:<br \/>\nZinc is electroplated on iron to prevent it from rusting.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 4.<br \/>\nWhy is distilled water a poor conductor of electricity?<br \/>\nAnswer:<br \/>\nBecause distilled water is free from any kind of salts.<\/p>\n<p>Question 5.<br \/>\nWhat effect does the current produce when it flows through a conducting solution?<br \/>\nAnswer:<br \/>\nCurrent causes chemical reaction when it flows through a conducting solution.<\/p>\n<p>Question 6.<br \/>\nWhat is galvanisation?<br \/>\nAnswer:<br \/>\nApplying a layer of zinc on an iron article by electroplating is called galvanisation.<\/p>\n<p>Question 7.<br \/>\nWhy is it dangerous to touch an electrical appliance with wet hands?<br \/>\nAnswer:<br \/>\nThis is because water can conduct electricity.<\/p>\n<p>Question 8.<br \/>\nWhat is LED?<br \/>\nAnswer:<br \/>\nIt is a semiconductor light source, used to detect a weak current in the circuit.<\/p>\n<p>Question 9.<br \/>\nDuring electrolysis of water, oxygen gas is deposited at which electrode?<br \/>\nAnswer:<br \/>\nPositive terminal or anode.<\/p>\n<p>Question 10.<br \/>\nDuring electrolysis of water, hydrogen gas is deposited at which electrode?<br \/>\nAnswer:<br \/>\nNegative terminal or cathode.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 11.<br \/>\nWhat is an electrolyte?<br \/>\nAnswer:<br \/>\nA substance which conducts electricity in the liquid state or when dissolved in water and breaks up chemically during the process is called an electrolyte.<\/p>\n<p>Question 12.<br \/>\nWhat is the practical use of LED?<br \/>\nAnswer:<br \/>\nThese are used in traffic lights and increasingly being used for lightning.<\/p>\n<p>Question 13.<br \/>\nDefine electric current.<br \/>\nAnswer:<br \/>\nThe amount of charge flowing per unit time is called electric current.<\/p>\n<p>Question 14.<br \/>\nName a liquid which does not conduct electricity.<br \/>\nAnswer:<br \/>\nDistilled water.<\/p>\n<p>Question 15.<br \/>\nWhat is the full form of LED?<br \/>\nAnswer:<br \/>\nLight emitting diode.<\/p>\n<p>Question 16.<br \/>\nWhich of these do you think uses less electrical energy-electric bulb or LED?<br \/>\nAnswer:<br \/>\nLED uses less electrical energy.<\/p>\n<p><span style=\"color: #0000ff;\">Short Answer Type Questions<\/span><\/p>\n<p>Question 1.<br \/>\nExplain the heating effect of electric current.<br \/>\nAnswer:<br \/>\nWhen an electric current passes through a conductor, it increases the temperature of the conductor. This is called heating effect of electric current. Many electrical appliances work on heating effect of electric current, e.g., electric bulb, water heater, electric iron, etc.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 2.<br \/>\nExplain the magnetic effect of electric current.<br \/>\nAnswer:<br \/>\nWhen an electric current passes through a conductor, a magnetic field is created around the conductor. This is called magnetic effect of electric current. This can be demonstrated by keeping a magnetic compass near a current-carrying conductor. A magnetic compass shows deflection when it is placed near a current-carrying conductor. The devices which work on magnetic effect of electric current are electric motor and electromagnet.<\/p>\n<p>Question 3.<br \/>\nWhat happens when electrodes are immersed in water and current is passed through it?<br \/>\nAnswer:<br \/>\nWhen electrodes are immersed in water and current is passed through it, bubbles of oxygen and hydrogen gases are produced. Oxygen bubbles are formed at the electrode connected to the positive terminal. Hydrogen bubbles are formed at the electrode connected to the negative terminal.<\/p>\n<p>Question 4.<br \/>\nDifferentiate between conductors and insulators.<br \/>\nAnswer:<\/p>\n<table border=\"2\">\n<tbody>\n<tr>\n<td style=\"text-align: center;\" width=\"141\">Conductor<\/td>\n<td style=\"text-align: center;\" width=\"141\">Insulator<\/td>\n<\/tr>\n<tr>\n<td width=\"141\">1. Substances which allow electric charge to flow through them are called conductors of electricity.<\/td>\n<td width=\"141\">1. Substances that do not allow electric charge to flow through them are called non-conductors or insulators of electricity.<\/td>\n<\/tr>\n<tr>\n<td width=\"141\">2. Examples: Metals like iron, copper, aluminium, etc.<\/td>\n<td width=\"141\">2. Examples: Rubber, wood, glass, etc.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Question 5.<br \/>\nDescribe an electrical tester.<br \/>\nAnswer:<br \/>\nAn electrical tester is a simple piece of electronic test equipment used to determine the presence or absence of an electric voltage in a piece of equipment under test. It is also used to test whether a liquid allows electric current to pass through it or not.<\/p>\n<p>Question 6.<br \/>\nWhy is water that we get from ponds and hand pumps always a good conductor of electricity?<br \/>\nAnswer:<br \/>\nWater that we get from ponds and hand pumps is not pure. It contains several amounts of mineral salts naturally dissolved in it, and thus is a good conductor.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 7.<br \/>\nDiscuss what happens when an electrolyte is dissolved in water, and then an electric current is passed through it.<br \/>\nAnswer:<br \/>\nWhen an electrolyte is dissolved in water, it breaks up into cations (positively charged ions) and anions (negatively charged ions). When an electric current is passed through the solution, the cations move towards the cathode (negatively charged electrode) and the anions move towards anode (positively charged electrode). This results in a chemical reaction or a chemical change.<\/p>\n<p>Question 8.<br \/>\nWhat is the application of the chemical effects of electricity in our daily life? Give examples.<br \/>\nAnswer:<br \/>\nExamples of chemical effect are as follows:<\/p>\n<ol>\n<li>Electroplating: A layer of one metal is coated on the other substance or metal by the effect of electric current. This is called electroplating.<\/li>\n<li>Electrolysis: The process by which a compound is decomposed into its constituents under the effect of electric current is called electrolysis.<\/li>\n<\/ol>\n<p>Question 9.<br \/>\nList some of the chemical effects of electric current.<br \/>\nAnswer:<br \/>\nWhen electric current is passed through a conducting solution, some chemical reaction takes place in the solution. This is called chemical effect of electric current. Some of the chemical effects of current are as follows:<\/p>\n<ul>\n<li>Bubbles of a gas may be formed at the electrodes.<\/li>\n<li>Deposits of metal may be seen on electrodes.<\/li>\n<li>Change of colour of solution may occur.<\/li>\n<\/ul>\n<p>Question 10.<br \/>\nIt is quite possible that even though a liquid allows electric current to pass through it and the circuit is complete but still the bulb does not glow? Why?<br \/>\nAnswer:<br \/>\nWhen current passes through a substance, it offers opposition to the flow of current. If the opposition offered by the substance is small, the current will be large and if the opposition is large, the current will be small. However, if the current through the circuit is too small, the filament of the bulb does not get heated up to a sufficient temperature and it does not glow.<\/p>\n<p><span style=\"color: #0000ff;\">Long Answer Type Questions<\/span><\/p>\n<p>Question 1.<br \/>\nWrite the steps involved in electroplating.<br \/>\nAnswer:<br \/>\nFollowing steps are involved in electroplating:<\/p>\n<ul>\n<li>The material which needs to be coated with a layer of desired metal is made the negative electrode (cathode).<\/li>\n<li>The plate of desired metal is made the positive electrode (anode).<\/li>\n<li>The conducting solution is made of a salt of desired metal.<\/li>\n<li>Electric current is passed through the solution.<\/li>\n<li>The electrolyte splits up releasing the ions of desired metal which get deposited at the cathode.<\/li>\n<li>An equal amount of the metal dissociates from the plate (anode) and gets dissolved in the electrolyte.<\/li>\n<\/ul>\n<p>Question 2.<br \/>\nWrite some uses of electroplating.<br \/>\nAnswer:<br \/>\nSome uses of electroplating are as follows:<\/p>\n<ul>\n<li>Imitation jewellery is made by applying a layer of gold or silver.<\/li>\n<li>Applying a layer of chromium on an article by this method is called chrome plating. Parts of bicycle, motorbike and sanitary fittings are chrome plated by this method.<\/li>\n<li>Tin cans are made by electroplating tin on iron.<\/li>\n<li>Applying a layer of zinc on an article is called galvanisation.<\/li>\n<\/ul>\n<p>Electric poles and beams on bridges are electroplated with zinc.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 3.<br \/>\nHow will you show experimentally that an electric current can bring about a chemical change? What is this phenomenon called?<br \/>\nAnswer:<br \/>\nTake two iron nails. Clean them with sandpaper. Wrap one or two rounds of copper wire around them and connect the other ends of the wires to the two terminals of an electric battery. Take water in a beaker and add to it a little salt or a few drops of sulphuric acid to make it conducting. Immerse the nails (called electrodes) in the solution. Observe the nails carefully.<\/p>\n<p>You can see small bubbles of gases coming out from the water near the nails. It can be checked that the gases evolved are hydrogen and oxygen. The gases come from water-electric current breaks up water into its constituent gases, hydrogen and oxygen. This observation, therefore, shows that electric current has a chemical effect on water. This experiment shows that an electric current can bring about a chemical change. This phenomenon is called electrolysis.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25945\" src=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-11.png?resize=338%2C323&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 11\" width=\"338\" height=\"323\" srcset=\"https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-11.png?w=338&amp;ssl=1 338w, https:\/\/i1.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-11.png?resize=300%2C287&amp;ssl=1 300w\" sizes=\"(max-width: 338px) 100vw, 338px\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 4.<br \/>\nDescribe how you will prepare a tester to test conduction based on the magnetic effect of electricity.<br \/>\nAnswer:<br \/>\nTake a tray of a discarded matchbox. Wrap an electric wire a few times around the tray. Place a smalt compass needle inside it. Now connect one free end of the wire to the terminal of a battery. Leave the other end free. Take another piece of wire and connect it to the other terminal of the battery. Join the free ends of the two wires momentarily. The compass needle should show deflection. The tester with two free ends of the wire is ready.<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25946\" src=\"https:\/\/i2.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-12.png?resize=337%2C296&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 12\" width=\"337\" height=\"296\" srcset=\"https:\/\/i2.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-12.png?w=337&amp;ssl=1 337w, https:\/\/i2.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-12.png?resize=300%2C264&amp;ssl=1 300w\" sizes=\"(max-width: 337px) 100vw, 337px\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 5.<br \/>\nComplete the following table.<\/p>\n<table border=\"2\">\n<tbody>\n<tr>\n<td style=\"text-align: center;\" width=\"98\">Liquid<\/td>\n<td style=\"text-align: center;\" width=\"92\">Compass needle shows deflection (Yes\/No)<\/td>\n<td style=\"text-align: center;\" width=\"94\">Conductor\/ Insulator<\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Lemon juice<\/td>\n<td width=\"92\">Yes<\/td>\n<td width=\"94\"><\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Vinegar<\/td>\n<td width=\"92\"><\/td>\n<td width=\"94\"><\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Tap water<\/td>\n<td width=\"92\"><\/td>\n<td width=\"94\"><\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Vegetable oil<\/td>\n<td width=\"92\"><\/td>\n<td width=\"94\"><\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Milk<\/td>\n<td width=\"92\"><\/td>\n<td width=\"94\"><\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Honey<\/td>\n<td width=\"92\"><\/td>\n<td width=\"94\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Answer:<\/p>\n<table border=\"2\">\n<tbody>\n<tr>\n<td style=\"text-align: center;\" width=\"98\">Liquid<\/td>\n<td style=\"text-align: center;\" width=\"92\">Compass needle shows deflection (Yes\/No)<\/td>\n<td style=\"text-align: center;\" width=\"94\">Conductor\/ Insulator<\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Lemon juice<\/td>\n<td width=\"92\">Yes<\/td>\n<td width=\"94\">Conductor<\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Vinegar<\/td>\n<td width=\"92\">Yes<\/td>\n<td width=\"94\">Conductor<\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Tap water<\/td>\n<td width=\"92\">Yes<\/td>\n<td width=\"94\">Conductor<\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Vegetable oil<\/td>\n<td width=\"92\">No<\/td>\n<td width=\"94\">Insulator<\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Milk<\/td>\n<td width=\"92\">No<\/td>\n<td width=\"94\">Insulator<\/td>\n<\/tr>\n<tr>\n<td width=\"98\">Honey<\/td>\n<td width=\"92\">No<\/td>\n<td width=\"94\">Insulator<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><span style=\"color: #0000ff;\">Picture-Based Questions<\/span><\/p>\n<p>Question 1.<br \/>\nDraw a well labelled diagram of passing current through water and answer the following questions.<br \/>\na. Which material is used as electrodes?<br \/>\nb. Name the material used to make caps of electrodes.<br \/>\nc. Name the gases formed.<br \/>\nd. Can we call the change in water as a chemical change?<br \/>\nAnswer:<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25947\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-13.png?resize=336%2C298&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 13\" width=\"336\" height=\"298\" srcset=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-13.png?w=336&amp;ssl=1 336w, https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-13.png?resize=300%2C266&amp;ssl=1 300w\" sizes=\"(max-width: 336px) 100vw, 336px\" data-recalc-dims=\"1\" \/><br \/>\na. Carbon rod is used as electrodes.<br \/>\nb. Brass caps or any other metal.<br \/>\nc. Oxygen and hydrogen.<br \/>\nd. Yes, it is a chemical change.<\/p>\n<p><img loading=\"lazy\" class=\"alignnone\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/01\/NCERT-Solutions-Guru.png?resize=170%2C17&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current\" width=\"170\" height=\"17\" data-recalc-dims=\"1\" \/><\/p>\n<p>Question 2.<br \/>\nObserve the following circuits carefully. In which circuit will the bulb glow?<br \/>\n<img loading=\"lazy\" class=\"alignnone size-full wp-image-25948\" src=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-14.png?resize=329%2C351&#038;ssl=1\" alt=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current 14\" width=\"329\" height=\"351\" srcset=\"https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-14.png?w=329&amp;ssl=1 329w, https:\/\/i0.wp.com\/mcq-questions.com\/wp-content\/uploads\/2021\/06\/NCERT-Solutions-for-Class-8-Science-Chapter-14-Chemical-Effects-of-Electric-Current-14.png?resize=281%2C300&amp;ssl=1 281w\" sizes=\"(max-width: 329px) 100vw, 329px\" data-recalc-dims=\"1\" \/><br \/>\nAnswer:<br \/>\na. No, because a rubber band is a poor conductor of electricity.<br \/>\nb. Yes, because iron key is a good conductor of electricity.<br \/>\nc. No, because pen is made of plastic which is a poor conductor of electricity.<br \/>\nd. Yes, because safety pin made of steel is a good conductor of electricity.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>These NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current Questions and Answers are prepared by our highly skilled subject experts to help students while preparing for their exams. Chemical Effects of Electric Current NCERT Solutions for Class 8 Science Chapter 14 Class 8 Science Chapter 14 Chemical Effects of Electric &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"\" href=\"https:\/\/mcq-questions.com\/ncert-solutions-for-class-8-science-chapter-14\/\"> <span class=\"screen-reader-text\">NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current<\/span> Read More &raquo;<\/a><\/p>\n","protected":false},"author":9,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"default","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"default","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","spay_email":""},"categories":[7],"tags":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v17.8 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current - MCQ Questions<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/mcq-questions.com\/ncert-solutions-for-class-8-science-chapter-14\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current - MCQ Questions\" \/>\n<meta property=\"og:description\" content=\"These NCERT Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current Questions and Answers are prepared by our highly skilled subject experts to help students while preparing for their exams. 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