The pH of a solution is the measure of hydrogen ion concentration in that solution. It is calculated by using the following mathematical equation:

`pH = - log_(10) [H^+]`

where, [H^+] is the concentration of hydrogen ions in the solution. When hydrochloric acid or HCl is in solution, it dissociates...

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The pH of a solution is the measure of hydrogen ion concentration in that solution. It is calculated by using the following mathematical equation:

`pH = - log_(10) [H^+]`

where, [H^+] is the concentration of hydrogen ions in the solution. When hydrochloric acid or HCl is in solution, it dissociates into hydrogen ions and chloride ions.

That is, `HCl -gt H^+ + Cl^-`

Here, the concentration of hydrochloric acid is given as 10^-8 M. Since 1 mole of HCl releases 1 mole of hydrogen ions, the concentration of hydrogen ions in the given solution is also 10^-8 M.

Thus, pH = `-log_(10) [H^+] = -log_(10) (10^-8) = 8.`

Thus, the 10^-8 M HCl solution has a pH of **8**.

Here, a very low concentration of acid is present, that is why the pH is above neutral. With high concentration of acids, pH is generally less than 7 and is in the acidic region.

Hope this helps.