Textbook Question
If a solution of HF 1Ka = 6.8 * 10-42 has a pH of 3.65, calculate the concentration of hydrofluoric acid.

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If a solution of HF 1Ka = 6.8 * 10-42 has a pH of 3.65, calculate the concentration of hydrofluoric acid.
A 0.100 M solution of chloroacetic acid 1ClCH2COOH2 is 11.0% ionized. Using this information, calculate 3ClCH2COO-4, 3H+4, 3ClCH2COOH4, and Ka for chloroacetic acid.
Phenylacetic acid 1C6H5CH2COOH2 is one of the substances that accumulates in the blood of people with phenylketonuria, an inherited disorder that can cause mental retardation or even death. A 0.085 M solution of C6H5CH2COOH has a pH of 2.68. Calculate the Ka value for this acid.