Using the Henderson-Hasselbalch equation, calculate the pH of an ammonia buffer when the NH₃:NH₄⁺ ratio is 0.4 moles:0.6 moles. (pK = 9.75)

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The Henderson-Hasselbalch equation is pH = pKa + log([A-]/[HA]), where [A-] is the concentration of the conjugate base and [HA] is the concentration of the acid. Given the ratio of [NH3]:[NH4+] is 0.4:0.6, we substitute these values and the given pKa of 9.75 into the equation: pH = 9.75 + log(0.4/0.6) = 9.75 + log(2/3) ≈ 9.07.

Using the Henderson-Hasselbalch Equation, Calculate the PH of an Ammonia