Question

How is the concentration of hydronium ions (H₃O⁺) affected when the solution of an acid is diluted?

Answer 1

When the solution of an acid is diluted, the concentration of hydronium ions decreases because the total volume of the solution increases on addition of water.

$\mathrm{Concentration}\mathrm{of}\mathrm{hydronium}\mathrm{ions}=\frac{\mathrm{Volume}\mathrm{of}\mathrm{solute}\left(\mathrm{acid}\right)}{\mathrm{Volume}\mathrm{of}\mathrm{solution}}$