If 15 ml of water is added to a solution of hydrochloric acid with a pH of 2, how will the solution change?

pH of the solution will slightly increase as it becomes less acidic for which it turns out to be more diluted.

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to calculate the pH change of the solution by firstly calculating the HCl concentration, as equal to that of the hydrogen ions whose pH is 2 as this is a strong acid:

Now, since water is added to the solution, but we do not have the initial volume of this solution, we can ensure that its pH will increase, become less acidic, because the concentration of the acid, and consequently that of the hydrogen ions, is diminished as the volume is increased.

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