One way to determine the pH of a buffer is by using the Henderson-Hasselbalch equation, which is pH = p _Kₐ_ \+ log([A⁻]/[HA]). In this equation, [HA] and [A⁻] refer to the equilibrium concentrations of the conjugate acid -base pair used to create the buffer solution. When [HA] = [A⁻], the solution pH is equal to the p _Kₐ_ of the acid.
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