<Li> pH is the acidity in the blood </Li> <Li> (HCO) is the concentration of bicarbonate in the blood, in mmol / L </Li> <Li> pCO is the partial pressure of carbon dioxide in the blood, in mmHg </Li> <P> The Henderson Equation, which is derived from the Law of Mass Action, can be modified with respect to the bicarbonate buffer system to yield a simpler equation that provides a quick approximation of the H or HCO concentration without the need to calculate logarithms: </P>

Free hydrogen ions in the blood plasma are neutralized by the formation of