Question

Does pure water conduct electricity? If not, what can we do to make it conduct?

Answer 1

Hint: To conduct electricity, there should be the mobile charges that are free to move in response to the applied electric field. The free electrons can be provided by the ionization process. Recall the ionization property of water to answer this question.

Complete answer:
We know that to conduct electricity, there should be the mobile charges that are free to move in response to the applied electric field. In metals, we see there are many mobile charges loosely bound to their atoms. When we apply electric fields across these metals, the charge carriers escape from the atoms and start to conduct the electricity.
In materials that are non-metallic, in our case, the pure water does not have loosely bound electrons. The electrostatic force of attraction between the water molecules is strong. When the electricity is passing through the pure water, it does not ionize the water molecule at a greater extent. We can see only about 2 molecules out of billions will be ionized at any given time. Thus, the pure water does not conduct electricity because it does not have free mobile electrons to move.
The water we drink regularly is not pure water. It has impurities which can conduct the electricity. If we add table salt in pure water, and let the electricity pass through, the common salt gets ionized quickly. Therefore, it starts conducting electricity.

Note:
Water also gets ionized into \[{{\text{H}}^ + }\] and \[{\text{O}}{{\text{H}}^ - }\], but the energy required to do so is huge. Without the excess energy, the rate of ionization is very slow. Thus, to answer this question, students must be familiar with the ionization process.