Question

1) What volume of water is required to dilute 30 mL of a nitric acid solution of pH 3 to pH 5?

2) 50 mL of a solution of pH 2 is added to 450 mL of water. What is the new pH?

Answer 1

well, pH is measured in denominations of 10. pH 3 is 10 times more acidic than pH 4, which is 10 times more acidic then ph5. You need to make it so the resulting solution has 100 times (percentage-wise) less acid than the 30mL of nitric acid.

If the solution was originally 50/50mL of an acid with pH2, then if that acid is now 50 our of (50+450)...you can do the math! Remember the denominations of 10.