Final answer:
To determine the pH of an 8.0×10⁻³ M HBr solution, we use the formula pH = -log [H3O+] and equal the [H3O+] to the acid concentration, yielding a pH of 2.10.
Step-by-step explanation:
To calculate the pH of a strong acid solution like HBr with a concentration of 8.0×10⁻³ M, you can assume complete dissociation into H+ (protons) and Br⁻ (bromide ions) because HBr is a strong acid. This means the concentration of H+ ions in the solution will be equal to the concentration of the acid. Therefore, the concentration of H3O+ will also be 8.0×10⁻³ M.
The pH is calculated using the formula pH = -log [H3O+]. Plugging in the concentration, we get:
pH = -log(8.0×10⁻³ M)
Using a calculator, this would give:
pH = 2.10