# What is a solution with a high concentration of hydrogen ions?

Oct 17, 2016

A solution with a high concentration of hydrogen ions (H^+) is an acid or an acidic solution. The higher the concentration of hydrogen ions (measured in mol/l or moles per litre) the stronger the acidity of the solution. This is usually measured in pH values calculating pH as $- \log \left[{H}^{+}\right]$. Any value below 7 (corresponding to ${10}^{-} 7 m o l / l$) is acidic.