An aqueous solution of HBrO₄ has a pH of 4.34. Find the molar concentration of HBrO₄ solution.

• A. 4.6 × 10⁻¹⁹ M
• B. 2.6 × 10⁻⁶ M
• C. 2.2 × 10⁻¹⁰ M
• D. 4.6 × 10⁻⁵ M

Answer: (D)

Verified step by step guidance

1. Understand that the pH of a solution is related to the concentration of hydrogen ions (H⁺) in the solution. The pH is defined as the negative logarithm (base 10) of the hydrogen ion concentration: \( \text{pH} = -\log[\text{H}^+] \).
2. Given the pH of the solution is 4.34, use the pH formula to find the concentration of hydrogen ions: \( [\text{H}^+] = 10^{-\text{pH}} \). Substitute the given pH value into the equation: \( [\text{H}^+] = 10^{-4.34} \).
3. Calculate the hydrogen ion concentration using the expression from the previous step. This will give you the molarity of H⁺ ions in the solution.
4. Recognize that for a strong acid like HBrO4, which dissociates completely in water, the concentration of H⁺ ions is equal to the initial concentration of the acid. Therefore, the molarity of HBrO4 is the same as the calculated [H⁺].
5. Compare the calculated molarity of HBrO4 with the given options to identify the correct answer. The correct molarity should match one of the provided choices.