Question

URGENT!

An aqueous solution at pH 9.0 has how many times more free OH- ions than H+ ions? How would you solve this?

Answer 1

pH of the aqueous solution = 9

Therefore, [H+] =
`10^(-9)` = 0.000000001 M

pH + pOH = 14

Therefore, pOH = 14 - pH = 14 - 9 = 5

[OH-] =
`10^(-5)` = 0.00001 M

Concentration of OH- ions is more than H+ ions by

`(0.00001)/(0.000000001) = 10,000` times

Thus, an aqueous solution at pH 9 has free OH-ions 10,000 times more than free H+ ions.