Acid rain, or acid precipitation is a term used to describe any form of precipitation with a pH of less than 5.6. In recent years, the effects of acid rain are being experienced on a global scale with widespread environmental effects. Primarily, acid rain is caused by emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) from the combustion of fossil fuels.
However, even pure rainwater is slightly acidic (pH of 5.6-6.5) due to the reaction between H2O and dissolved CO2 which produces a weak carbonic acid, H2CO3.
1.2 Issue
Acid rain is the result of water droplets in clouds absorbing sulfur dioxide and nitrogen oxides emitted from the surface of the earth as a result of both natural and man-made processes. …show more content…
Organisms such as fish can maintain their internal pH in water that has a pH in the range of 6.5-8.5 (Principles of General Chemistry, 2012). When acid rain decreases the external pH, many aquatic organisms can no longer maintain their internal pH and die. Even slight imbalances in the pH of the aquatic system can result in a decline in population of fish eggs and young which in turn affects the population of the animals higher up the food chain. Sulfuric acid in lakes and rivers interferes with the fish’s ability to take in oxygen, salt and nutrients that are essential to its survival.
1.5.2 Effects of acid rain on plant life
The effects of acid rain on plant life is less subtle than in aquatic biomes. The direct effects of acid rain on plant life include dissolving leaves and leeching essential minerals and nutrients needed for healthy functioning. Trees and many other plants are affected by the presence of aluminum and other metals in groundwater. At stable pH levels, Aluminum hydroxide [Al(OH3)] present in soil, is insoluble. However, at lower levels of pH, Aluminum hydroxide dissolves by the following reaction:
1.5.2.1 Equation
Al(OH)3(s) + 3H+(aq) → Al3+(aq) +