In an aqueous solution thee [OH-] is 1.0 x 10^{- 6} M. What is the [H⁺]? A) 1.0 × 10^-9 M B) 1.0 × 10^-8 M C) 1.0 × 10^{- 6} M D) 1.0 × 10⁸ M

Question

Quizplus · Accepted Answer

For a neutral solution, [H+] = [OH-]. When [OH-] is given as 1.0 x 10^-6 M, we can find [H+] as follows:

[H+][OH-] = 1.0 x 10^-14 M^2 (from Kw)
[H+] = (1.0 x 10^-14 M^2) / (1.0 x 10^-6 M)
[H+] = 1.0 x 10^-8 M

Since the solution is basic (due to [OH-] being greater than [H+]), we can use the following equation to find [HS+]:

Kw = [H+][OH-] = [HS+][OH-]/[S2-]
[S2-] = [OH-] - [HS+]

Substituting the values we know, we get:

1.0 x 10^-14 M^2 = [HS+](1.0 x 10^-6 M) / ([OH-] - [HS+])
1.0 x 10^-14 M^2 = [HS+](1.0 x 10^-6 M) / (1.0 x 10^-6 M - [HS+])
1.0 x 10^-8 M - [HS+] = [HS+]
[HS+] = 5.0 x 10^-9 M

Therefore, [HS+ + S2-] = [HS+] + [OH-] - [HS+] = [OH-] = 1.0 x 10^-6 M

Thus, the answer is B) 1.0 × 10^-8 M.

In an Aqueous Solution Thee [OH-] Is 1