Question

Poor conductors of electricity is/are:
(a) Silver
(b) Aluminium
(c) Pure water
(d) Copper

Answer 1

Hint: In this question use the concept that a substance is a poor conductor of electricity. Is there no free electrons or no free charges that can move across the lattice. So choose the option that doesn't have free electrons. This will help get the right answer.

Complete Step-by-Step solution:
Materials that are poor conductors of electricity are called insulators.
Some examples are wood, glass, plastics, non-metal elements that are polymers of hydrocarbons.
The reason that they do not conduct electricity is that charges cannot move through them the particles and their electrons are locked into a solid structure.
So among the following options aluminum, silver and copper are metals and these are good conductors of electricity.
So the only option remaining is pure water, pure water is a poor conductor since its molecules do not have free electrons to travel and thus transfer current.
But always remember that salty water or impure water is a good conductor of electricity.
So this is the required answer.
Hence option (C) is the correct answer.

Note – The trick point is that mostly all the metals are very good conductors of electricity, so silver, aluminum and copper being in the category of metals, can’t be insulators, thus they get eliminated in the very first sight only. Another main reason behind pure water being an insulator is that it is free from dissolved minerals and these minerals act as metals and are responsible for conduction. So absence of these make pure water non-conducting.