Acid Deposition and Oxidant Research Center
Asia Center for AirPollution Research(ACAP)
Global environmental
Mechanism of acid deposition
Impacts of acid deposition
pH of rain
Energy consumption and acid deposition
Consumption of natural resources and acid deposition
Research Activity
e-learning course

4. pH of rain

pH is one of the important indices of rain. However, the relationship between pH value and acid concentration, in other words, the concentration of hydrogen ion, is rather complex. The lower the pH value is, the higher the hydrogen ion concentrations are. Hydrogen ion concentrations increase more rapidly in lower pH values. pH values depend on the balance of acid and base. Even if rain contains a high concentration of nitric and sulfuric acids and has a low pH, the pH value will become higher with more bases like ammonium. We, therefore, may have problems with rain with high pH. We need to pay due attention to the concentrations of sulfuric and nitric acids as well.


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