pH is a measure of the concentration of hydrogen ions (mol dm^-3) in a solution.

Use the following equation to calculate pH when the concentration of H⁺ is known:

\(pH = - \log_{10}{[H^+]} \)

This can be rearranged into the following equation, which is used to calculate the concentration of H⁺ when the pH is known:

\([H^+] = 10^{-pH} \)