Question

which of the following do not conduct electricity?
A. Distilled water
B. Rain water
C. Sea water
D. Iron rod

Answer 1

Hint: On the basis of conducting the electricity substances can be classified into conductors, semiconductors and insulators. Electricity occurs if there is a free flow of electrons in a substance.

Complete answer:
The flow of electric charge causes electricity where we know that charge is a property of matter. It can be measured and has a concept of positive and negative charge. Charge carriers are subatomic particles that carry charge. We know that an atom is composed of protons, electrons and neutrons which carry positive, negative and neutral charge respectively.
Ions are charged particles that do not have an equal composition of electrons and protons. Now let us analyze each option one by one, the substance with neutral particles will not conduct electricity. So we know that sea water is saline in nature therefore electricity can pass through it as it has ions in it, similarly rain water also has impurities and ions which conduct electricity.
Iron rod has metal iron in it which has free electrons in it that cause flow of charge on
passing electricity through it. Therefore only distilled water does not cause electricity hence it is an insulator because it is purified and does not contain any impurities whereas all the above are conductors.

Hence the correct option is A.

Note: Semiconductors behave like insulators at the temperature of 0 K. but at a higher temperature, a small number of electrons are able to free themselves and they respond to the applied electric field.