explain why HCO3 levels can be calculated from pH and pCO2 l

explain why HCO3- levels can be calculated from pH and pCO2 levels

Solution

pH is defined as the negative log of the Hydrogen ion concentration: -log[H+].

(also, pH=pK+log [HCO3]/ 0.03 x pCO2). The pH is the product of two components,
respiratory and metabolic, thus allowing for the effect of the pCO2, ie, any change in the pH unexplained by the pCO2 resulting in a metabolic abnormality.

CO2 and water combine to form carbonic acid or H2CO3, present with concentrations of bicarbonate (HCO3-)and hydrogen ions (H+) in equilibrium amounts. A change in the concentration of the reactants on either side of the equation affects the subsequent direction of the reaction. Eg., a rise in CO2 will also raise carbonic acid formation (H2CO3) which leads to raised levels of both HCO3- and H+ (\\pH).