What is the pH of a solution in which the hydroxide ion concentration is equal to 9.1 x 10^-2 moles/liters.
A
Acid
B
Basic
C
Neutral
D
Neither
(H^+)(OH^-) = 1E-14
Solve for (H^+), then
pH = -log(H^+).
If pH
<7 = acid
7 = neutral
>7 = basic.
To determine the pH of a solution, you can use the formula:
pH = -log[H+]
where [H+] represents the concentration of hydrogen ions in moles per liter.
In this case, we are given the concentration of hydroxide ions ([OH-]), not hydrogen ions. The two ions are related by the equation: [H+] * [OH-] = 1.0 x 10^-14 at 25°C.
To find the concentration of hydrogen ions [H+], we can rearrange the equation:
[H+] = 1.0 x 10^-14 / [OH-]
Substituting the given value of [OH-] = 9.1 x 10^-2 moles per liter:
[H+] = 1.0 x 10^-14 / (9.1 x 10^-2)
[H+] ≈ 1.09 x 10^-13 moles per liter
Now, we can calculate the pH using the formula mentioned earlier:
pH = -log(1.09 x 10^-13)
Using a scientific calculator or similar tool, the pH is approximately 12.96.
Since the pH value is greater than 7, the solution is considered basic (B).