Equation used to calculate pH of acidic buffer solution is: pH = pKa + log [salt] / Acid Which of the following is correct about this equation:
Correct answer: A. pH = pKa when[acid] = [salt]
- A. pH = pKa when[acid] = [salt]
- B. pH > pKa when [acid ]> [salt]
- C. pH > pKa when [acid] > [salt]
- D. All of these
Explanation
For the given expression the correct realtions are: pH>pKa when [salt] > [ Acid] pH<pKa when [salt] <[Acid] When the concentration of the acid ([acid]) is equal to the concentration of the salt ([salt]), the ratio [salt]/[acid] becomes 1, and the logarithm of 1 is 0. Therefore, the pH of the acidic buffer solution will be equal to the pKa. Thus, option A is correct.
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