As a chemical engineer with a focus on material science, I can provide an in-depth analysis of the electrical conductivity of pure water.

Electrical conductivity is the measure of a material's ability to conduct an electric current. In the case of pure water, the electrical conductivity is extremely low. This is because pure water is composed of H2O molecules, which do not readily dissociate into ions. The process of dissociation is the key to electrical conductivity, as it involves the separation of molecules into charged particles, or ions, which can move freely and carry an electric current.

The statement that "The current flow through pure water is negligible" is accurate. Pure water lacks the ions necessary for significant electrical conductivity. However, it's important to note that even in pure water, there is a very small degree of self-ionization, where a tiny fraction of water molecules will dissociate into hydrogen ions (H+) and hydroxide ions (OH-). This self-ionization is represented by the equilibrium equation:

\[ \text{H}_2\text{O} \rightleftharpoons \text{H}^+ + \text{OH}^- \]

However, the concentration of these ions is very low, typically on the order of 10^-7 M, which is not sufficient to support a significant flow of electric current.

When discussing the addition of substances like HCl to water, we are talking about the introduction of a strong electrolyte. HCl is a strong acid that completely dissociates in water into hydrogen ions (H+) and chloride ions (Cl-), as shown in the following equation:

\[ \text{HCl} \rightarrow \text{H}^+ + \text{Cl}^- \]

This dissociation significantly increases the concentration of ions in the solution, which in turn increases its ability to conduct electricity. The presence of these additional ions allows for the movement of charge, thus facilitating the flow of electricity.

To summarize, pure water has a very low electrical conductivity due to the lack of free ions. The addition of a strong electrolyte like HCl dramatically increases the conductivity of the solution by providing a large number of ions that can move and carry an electric current.

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The current flow through pure water is negligible. A solution conducts current when positive and negative ions are randomly dissolved in it. Pure water doesn't have enough ions but when you add HCl you add a strong electrolyte so, after the addition, solution can conduct electricity very well.read more >>