i. Most liquids that conduct electricity are solutions of acids, bases and salts.
ii. The passage of an electric current through a solution causes chemical effects.
iii. If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the negative terminal of the battery.
iv. The process of depositing a layer of any desired metal on another material by means of electricity is called electroplating.
i. A piece of fresh potato does not conduct electricity. F
ii. LED glows even when a low electric current passes through it. T
iii. The passage of an electric current through a conducting solution causes chemical effect. T
iv. Materials such as rubber plastic and wood conduct electricity. F
Ans. Chromium is usually electroplated on bathroom fittings.
Ans. No, some liquids are good conductors of electricity and some are poor conductors.
Ans. Bubbles of gases are formed when an electric current is passed through acidified water.
Ans. Water is decomposed into hydrogen and oxygen by passing electric current through it.
Ans. Liquids such as vinegar, lemon juice, tap water, rain water and sea water conduct electricity.
Ans. Liquids such as water, milk, vegetable oil and honey do not conduct electricity.
Ans. Though vinegar and lemon juice conduct electricity but they are weak conductors of electricity.
Ans. The process of depositing a layer of any desired metal on another material by means of electricity is called electroplating.
Ans. Even if the current is small, the deflection of the magnetic needle can be seen.
Ans. LED (Light Emitting Diodes) glows even when a weak electric current flows through it.
Ans. The conducting solution used in the electroplating process is the polluting waste generated by electroplating factories.
Ans. The advantage of using LED in testing the electrical conductivity of liquids is that it glows even when a weak electric current flows through it.
Ans. Pure water is free of salts and is a poor conductor. We can add some common salt in pure water to make it conducting.
Ans. Silver and gold are usually electroplated on cheaper metals for making jewelry (or ornaments).
Ans. Magnetic effect of electric current is utilized for detecting the flow of current through a solution when a compass is used.
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