When electric current is passed through water containing acid, ____ gases are produced.
A) hydrogen and oxygen
B) hydrogen and ozone
C) oxygen and hydrogen peroxide
D) hydrogen peroxide and ozone
When a soluble metallic salt is added to water, its electrical conductivity decreases.
Materials that allow electricity to pass through them are called ____.
Materials that do not allow electricity to pass through them are called ____.
A tester is used to test the conduction of electricity through two liquids, labelled A and B. It is found that the bulb of the tester glows bright for liquid A, while it glows very dimly for liquid B. We can conclude that liquid A is a better conductor than liquid B.
The device used to test whether a particular material allows electric current to pass through it or not is a ____.
While checking your tester, do not join its free ends for more than a few seconds, otherwise the cells of the battery will drain very quickly.
Which of the following liquids is a poor conductor of electricity?
A) Lemon juice
C) Sugar solution
D) Salt solution
Which amongst the following is a poor conductor of electricity?
B) Common salt solution
C) Copper sulphate solution
D) Aqueous solution of HCl
Why doesn't the bulb of a tester glow sometimes even though the material may be a conductor?
A) The current through the circuit is too weak.
B) The current through the circuit is sufficient.
C) The filament gets heated to a very high temperature.
D) The conductor is weak.