Chemical effects of electric current Worksheet-4

Chemical effects of electric current Worksheet-4

 

  1. Give two examples of good conductors of electricity.

 

  1. Why is it dangerous to touch an electrical appliance with wet hands?

 

  1. What are insulators (poor conductors) of electricity?

 

  1. Give two examples of poor conductors of electricity.

 

  1. What is electric current?

 

  1. Do liquids conduct electricity?

 

  1. How can you check current?

 

  1. Give any liquid conductor.

 

  1. Can distilled water conduct electricity?

 

  1. How can we test that liquids conduct electricity?

 

  1. Name some substances which make the liquids good conductor of electricity.

 

  1. Name two liquid substances other than water which conduct electricity.

 

  1. Sometimes even though the liquid is conducting the bulb may not glow. Give reason.

 

  1. Which effect of current causes the bulb to glow?

 

  1. Name the part of bulb which glows.

 

  1. What is LED?

 

  1. Write full form of LED.

 

  1. What are the three effects of electric current?

 

  1. What is magnetic effect of electric current?

 

  1. What happens when a compass needle is brought near a wire in which current is flowing?

 

  1. How can we check magnetic effects of current?

 

  1. Does distilled water conduct electricity?

 

  1. How can we make distilled water a good conductor of electricity?

 

  1. What is distilled water?

 

  1. Name a salt which makes distilled water a good conductor of electricity.

 

  1. What are electrodes?

 

  1. Name the gases which release when current is passed through water.

 

  1. Name the gas deposited on negative electrode

 

  1. Name the gas deposited on a positively charged electrode.

 

  1. Name the process show the chemical effect of electricity.

 

Answer:

  1. Copper, iron.

 

  1. Wet hands act as good conductors. So we may feel electric shocks when we touch electric appliance with wet hands.

 

  1. The materials which do not allow electric current to pass through them are called poor conductors or insulators.

 

  1. Dry wood, rubber.

 

  1. The flow of charge (electricity) is called electric current.

 

  1. Yes

 

  1. by using tester

 

  1. Tap water

 

  1. No

 

  1. We use tester to check that the liquids conduct electricity.

 

  1. Acids, Bases and Salts.

 

  1. (i) Lemon Juice (ii) Vinegar

 

  1. May be the current passing  through it too weak to make the bulb glow.

 

  1. Heating effect

 

  1. Filament

 

  1. LED is a device or bulb which even glow at low or small current.

 

  1. Light Emitting Diode.

 

  1. heating, magnetic and chemical effect.

 

  1. The electric current also produces the magnetic effect in which a current carrying wire behaves like a magnet.

 

  1. The needle deflects

 

  1. By using magnetic compass

 

  1. No

 

  1. By adding some salt in it

 

  1. The water which is free of salts

 

  1. Common salt

 

  1. The metal rods dipped in liquids to which cells are attached are called electrodes.

 

  1. Hydrogen and oxygen

 

  1. Hydrogen

 

  1. Oxygen

 

  1. Electroplating