What is ACID RAIN?

Acid rain is a phenomenon that has caused many problems in recent years. Some problems are caused the change in pH in soils of rural areas and the destruction of steel structures, churches and historical monuments of marble.

The formation of acid rain is caused mainly by burning fossil fuels. Combustion are formed in the acid oxides of sulfur and nitrogen derivatives of general formula SOx and NOx These gases by reacting with water present in atmospheric air will form what we call acid rain.

One of the most complicated is the decrease of soil pH, decreasing fertility by making it unprofitable for the planting of some species. One way of doing is correct liming the soil, which consists of adding lime (CaO) to the ground. When this is added, the following reaction occurs:

CaO + H2O → Ca +2 + 2OH-

The OH-ions released will make a correction of pH.

The destruction of statues in marble is another serious problem caused by rain, as many have a historical value unimaginable. This destruction is by the reaction of acids with marble (CaCO3), as can be seen in the reaction:

CaCO3 + 2H + → Ca +2 + H2O + CO2

See some photos ;