Question

How does the PH of the solution change when a solution of base is diluted?

Answer 1

Dilution changes the pH value of an acid or a base toward 7. The pH value of  a acidic solution increases with dilution and the pH values of a basic solution decreases with dilution. It is because by dilution the concentration of the H+ ions of an acid reduces and by dilution the concentration of the OH- ions of a base reduces.
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Answer 2

Ans. The pH of a basic solution is greater than 7 but when the solution is diluted the basic pH reduces to be like as in pure water that is closer to 7.So, when the solution is diluted its PH value decreased for basic solution and increase for acidic solution that is nearly 7 that is pure water.
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