MCQ Class 8 Science Chapter 11 Chemical Effects of Electric Current Advertisement MCQ’s For All Chapters – Science Class 8th 1. Why do we add little dilute sulphuric acid to copper sulphate solution during electroplating?To burn copper SulfateTo increase acidityTo increase conductivitySo that the colour becomes more prominentQuestion 1 of 182. A coating of _________is deposited on iron to protect it from corrosion and formation of rustcoppersilverZincAluminium Question 2 of 183. Chromium plating is done on many objects such as car parts, bath taps, kitchen gas stove etc. Why?Articles can be sold at higher priceIt does not corrode but prevents scratchesIt looks beautifulIt costs lessQuestion 3 of 184. The process of depositing a layer of any desired metal on another material by means of electricity is called ___________.Electric depositingElectric platingElectroplatingNone of the aboveQuestion 4 of 185. Some liquids are good conductors of electricity and some are poor conductors. Which one is a poor conductor?Distilled waterAcidic solutionAlkaline solutionCommon Salt solutionQuestion 5 of 186. Tin cans, used for storing food, are made by electroplating tin onto iron. Why?To make the vessel cheapTo make the vessel lighterTin is less reactive than iron.Tin gives a shiny appearanceQuestion 6 of 187. Current is the flow of:neutronselectronsprotonsnone of theseQuestion 7 of 188. When electric current is passed through the copper sulphate solution, copper sulphate dissociates into:copper and sulphatecopper and sulphurcopper and oxygennone of theseQuestion 8 of 189. The cans, used for storing food, are made by electroplating ……………. on to ironstinchromiumzincnone of theseQuestion 9 of 1810. ……………….. is deposited on Iron used in bridges and automobiles to protect it from corrosion and formation of rust.ChromiumlinZincNone of theseQuestion 10 of 1811. Car parts, bath taps, kitchen gas burners, bicycle handlebars are electroplated with:tinchromiumzincnone of theseQuestion 11 of 1812. 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 white it glows very dimly for liquid H. You would conclude that:conducting properties of liquid cannot be compared in this mannerliquid B is a better conductor than liquid Aliquid A is a better conductor than liquid Bboth liquids are equally conductingQuestion 12 of 1813. Which one is the conductorleatherbrassplasticmicaQuestion 13 of 1814. The process in which a chemical change takes place in a substance, when electric current is passed through it is called:thermal conductionelectrolysiselectrodesnone of theseQuestion 14 of 1815. We use magnetic needle to find the effect of:magnetismslow electric currentsmall electric currentnone of theseQuestion 15 of 1816. Which liquid do not conduct electricity?distilled watercommon salt solutionacidic solutionnone of theseQuestion 16 of 1817. Adding lime water to tap water makes it:no change occuran electrolyteelectrolysisnone of theseQuestion 17 of 1818. The positive charged ions are called:ionscationsanionsnone of theseQuestion 18 of 18 Loading...
Very excellent questions and answer