Henderson-Hasselbalch Calculator

What is this calculator used for?

The Henderson-Hasselbalch Calculator helps determine the pH of a buffer solution using the well-known Henderson-Hasselbalch equation. It's particularly useful in chemistry and biology for estimating pH in buffer solutions made from weak acids and their conjugate bases.

How to use this calculator?

1. Enter the pKa value of the weak acid.
2. Input the concentration of the acid.
3. Input the concentration of the conjugate base.
4. Click "Calculate pH" to see the result.

Formula Used

Henderson-Hasselbalch Equation:
pH = pKa + log₁₀( [Base] / [Acid] )

Example

Suppose you have a buffer with a pKa of 4.75, a conjugate base concentration of 0.1 mol/L, and an acid concentration of 0.05 mol/L.
Then,
pH = 4.75 + log₁₀(0.1 / 0.05) = 4.75 + log₁₀(2) ≈ 4.75 + 0.3010 = 5.05