Extra questions answers on chemical effect of current class8
Answers
name the non metal which is liquid
Answer:
Very Short Answer Questions
Question 1.
What are good conductors?
Answer:
The substances that conduct electricity through them are called good conductors.
Question 2.
What are insulators or poor conductors?
Answer:
The substances that do not conduct electricity through them are poor conductors or insulators.
Question 3.
Give four examples of conductors.
Answer:
Copper, iron, aluminium and brass.
Question 4.
Give four examples of insulators.
Answer:
Air, wood, rubber and plastic.
Question 5.
Name two metal objects which have a coating of another metal.
Answer:
Handlebars of bicycles, bathroom taps.
Question 6.
What do we get on electrolysis of acidified water?
Answer:
Hydrogen and oxygen gas.
Question 7.
Is air a bad or good conductor?
Answer:
A bad conductor.
Question 8.
Which metal is plated on handle bars of cycles and rim of wheels?
Answer:
Chromium
Question 9.
What is the full form of LED?
Answer:
Light Emitting Diode.
Question 10.
How do we check the electric current?
Answer:
We check the electric current by using a tester.
Question 11.
Which part of an atom is responsible for flow of current?
Answer:
Electron
Question 12.
Why do most liquids conduct electricity?
Answer:
Due to the presence of ions in them, most liquids conduct electricity.
Question 13.
An LED is more efficient device than a bulb. Why?
Answer:
LED is more efficient because it can glow even when a weak or less current flows through it.
Explanation: