Henderson-Hasselbalch Calculator

Henderson-Hasselbalch Calculator determines the pH of a buffer solution quickly and effortlessly. This free tool takes conjugate base, acid, Ka details to give the concentration of the acid and conjugate base within it.

Conjugate Base[HA-]

Henderson-Hasselbalch Equation Calculator: Do you wanna learn more about the acid concentration in a buffer solution? If so, you have reached the correct page that gives the pH of a buffer solution. Read on to get what is the Henderson-Hasselbalch equation, its derivation and how to calculate the concentration of the acid. Also, check the solved example questions in the following sections.

Step by Step Process to Find pH

Go through the steps on how to calculate the pH of the solution easily.

  • Get the conjugate base, acid, Ka details.
  • Divide the conjugate base by the acid.
  • Find the logarithm of the value
  • Add it to the pKa to get the solution pH.

Henderson-Hasselbalch Equation

The Henderson-Hasselbalch Equation to calculate the pH of the solution is as follows:

pH = pKₐ + log([A⁻]/[HA])

The parameters required to use the Henderson-Hasselbalch Calculator is along the lines:

[A⁻] is the molar concentration of the conjugate base

[HA] is the molar concentration of the acid

pK is the acid's dissociation constant

The pH formula is pH = -log(H).

A buffer solution contains a strong acid with a weak conjugate base, strong base with a weak conjugate acid.

In simple terms, the acid can be defined as the proton donor. The base is a proton acceptor.


Question: A mixture of 0.2 M acetic acid and 0.3 M sodium acetate is given. Calculate the pH of the medium if pKa of the acid is 4.5.


Given that

The concentration of acetic acid = 0.2 M

The concentration of the acetate ion = 0.3 M

pka of aetic acid = 4.5

pH = pKₐ + log([A⁻]/[HA])

pH = 4.5 + log(0.3/0.2)

= 4.5 + log 1.5

= 4.5 + 0.18

= 4.68

The pH of the given solution is 4.68.

Chemistrycalc.Com has got calculators like Buffer Capacity, Buffer pH, Cell EMF and many more at one place.


FAQ’s on Henderson-Hasselbalch Calculator

1. What is the use of the Henderson-Hasselbalch equation?

The Henderson-Hasselbalch equation is used for calculating the amount of acid or conjugate base to be required for preparing the buffer solution that has a specific pH.

2. How to solve the Henderson-Hasselbalch equation without using a calculator?

The Henderson-Hasselbalch equation is pH = pKₐ + log([A⁻]/[HA]). Place the values in the formula and solve to get the concentration of acid in a buffer solution.

3. What is the pK value?

pK is the measure of the strength of the acid on a logarithmic scale and it is used to compare the strength of various acids. pK = log(1/Ka). Here Ka is the acid dissociation constant.

4. What is the relationship between pK and pKa?

The simple relationship between the pK and pKa is pKa + pKb = 14.