How many mL of water must be added to $250 mL$ of a strong acid solution of pH $2$ to change its pH to $4$ (volumes additive)? Give the answer to the nearest integer.

Numerical answer type, answer in mL, tolerance 1.

Answer: 24750 mL

Two pH units means

[H X^{+}]

falls

100

-fold, so the final volume is

250 \times 100 = 25000 mL

. Water to be added

= 25000 - 250 = 24750 mL