Final answer:
The hydronium ion concentration [H3O+] of a solution with a pH of 9.50 is 3.16 × 10-10 M, and the hydroxide ion concentration [OH-] is 3.16 × 10-5 M. These concentrations have been calculated based on the pH and the relationship between pH and pOH.
Step-by-step explanation:
To calculate the hydronium ion concentration [H3O+] for a solution with a pH of 9.50, we use the formula pH = -log[H3O+]. We reverse the operation to solve for [H3O+]:
[H3O+] = 10-pH
[H3O+] = 10-9.50
[H3O+] = 3.16 × 10-10 M
The concentration of hydroxide ions [OH-] can be found using the relationship 14 = pH + pOH and [H3O+] × [OH-] = 1 × 10-14 at 25 °C. We first calculate pOH:
pOH = 14 - pH
pOH = 14 - 9.50
pOH = 4.50
Then we calculate [OH-]:
[OH-] = 10-pOH
[OH-] = 10-4.50
[OH-] = 3.16 × 10-5 M
The [H3O+] of a solution with a pH of 9.50 is 3.16 × 10-10 M, and the [OH-] is 3.16 × 10-5 M. Both answers have two significant figures, in accordance with the given pH value.