Difference Between Total Alkalinity and pH l Total Alkalinity vs pH

The key difference between total alkalinity and pH is that total alkalinity is the total concentration of all alkaline substances dissolved in water whereas pH is the minus log of the concentration of hydrogen ions in water.

Most of the times, we confuse with the two terms total alkalinity and pH because both these terms are equally useful in aquatic chemical determinations. Indeed, these two terms relate to each other, but they are not the same. Thus, there exist a definite difference between total alkalinity and pH


1. Overview and Key Difference
2. What is Total Alkalinity
3. What is pH
4. Side by Side Comparison – Total Alkalinity vs pH in Tabular Form
5. Summary

What is Total Alkalinity?

Total alkalinity is the water’s ability to resist changes in pH. In other words, it is the measurement of total concentration of all the alkaline species dissolved in water. The principle alkaline species include hydroxide ions, carbonate and bicarbonate ions. These ions can buffer the pH of water by neutralizing acids, that’s why we can say that the total alkalinity is the ability of water to resist the changes in pH.