Question

what is effect of dilution on h+ ion concentration of an acid

Answer 1

A given solution of an acid is diluted by adding more water. Thus, the overall volume of the solution increases. However, the number of hydrogen ions in solution remain the same. Therefore, the number of hydrogen ions per unit volume decreases and hence the concentration of hydrogen ions decreases.

Answer 2

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When an acid us diluted its H+ ion concentration decreases, whereas its OH- ion concentration increases. This in turn leads to an increase in pH value too.