explain the difference between distilled water and tap water in terms of conductivity?

Question

explain the difference between distilled water and tap water in terms of conductivity. Explain your answer please.

Answer 1

Distilled water has all the minerals and all the dissolved gases removed. There is nothing in it to allow electricity to be conducted.

Tap water may or may not conduct electricity depending on the level of mineral content. It is the dissolved minerals that cause the water to conduct. Most tap water contains a sufficient abount of dissolved minerals to signficantly conduct electricity.

Answer 2

In order for something to conduct electricity it must have something to carry charges.

Actually distilled water self dissociates according to the reaction
2H2O <=> H3O+ + OH-
At room temperature the equilibrium constant is Kw=10^-14 and the concentrations of the ions is very small [H+]=[OH-]=10^-7M.
That's why it is an extremely poor conductor.

Tap water contains several different types of salts. These have already dissociated into ions which carry charges and thus the motion of the ions is the mechanism for conducting electricity. Also there will be ions coming from CO2 dissolved in tap water. Freshly prepared destilled water will have no CO2 but as time passes CO2 will start dissolving, produce ions and increase the conductivity.

Answer 3

Tap water will conduct electricity better than distilled water because of the presence of impurities, some of which are ionic compounds, which add to conductivity.

Answer 4

Distilled water has no ions in it, and thus free electrons, making it a very poor conductor.

Tap water has lots of metals, salts and impurities that contain ions allowing it to conduct electricity, and salt water would conduct electricity even better.