How to Calculate pH of a Weak Acid Solution
What is the predicted pH of a 0.19 M solution of a weak acid?
Given the Ka of a weak acid is 1.81 x 10⁻⁵, how can we determine the pH of a 0.19 M solution of the weak acid?
The pH of a 0.19 M solution of a weak acid with Ka of 1.81 x 10⁻⁵
The pH of a 0.19 M solution of a weak acid with Ka of 1.81 x 10⁻⁵ can be calculated using a simple formula.
When dealing with weak acids, the Ka value indicates the degree of ionization in the solution. To find the pH of a 0.19 M solution of a weak acid with a Ka of 1.81 x 10⁻⁵, we can use the formula:
pH = -log(square root of (Ka x Molarity))
Substitute the values into the formula:
pH = -log(sqrt(1.81 x 10⁻⁵ x 0.19))Now, calculate the pH using the formula:
pH = -log(sqrt(0.000003439)) pH = -log(0.001856) pH = 2.73Therefore, the predicted pH of a 0.19 M solution of a weak acid with a Ka of 1.81 x 10⁻⁵ is 2.73.