One of the results of man’s impact on the environment is that the pollutants he releases lead to acid rain and alkaline rain, which have significant effects on the environment.
Acid rains are usually loade with sulphur and carbon dioxide , while alkaline rains though not so common but rains laded soil dusts innform of aerosols . Impact of alkaline rains is more detrimental than acid rains on plant growth...
Rainwater is naturally slightly acidic and has an average pH of 5.6. Rain is therefore considered acidic when its pH is below 5.
The root cause of acid rain is air pollution. Some of the gas in the air dilutes in raindrops and produces acid. CO2 or carbon is thus transformed into carbonic acid, and its presence in rainwater is natural. This phenomenon explains the slight acidity of rain compared to water.
If the dose of pollutants in the air increases or changes, on the other hand, the acidity of the rainwater can do the same. However, human activities and their releases into the atmosphere have drastically worsened air pollution over the past century, adding nitric or sulfuric acid to rainwater.
The acidity of the rain affects everything it touches.
The flora is generally the most impacted since the most exposed: acid rain kills many species, renders others sterile and weakens the last. They thus promote the appearance of diseases in survivors or make them susceptible to attacks by insects and fungi. Part of the degradation of the Black Forest in Germany is due to acid rain. As for the soils, impoverished and stripped, they produce less and less well, disrupting agriculture, horticulture and plant development in general.
Acid rain pollutes the waters it falls into, especially lakes and rivers. They make them toxic, disrupting the entire ecosystem around them, from the fish that live there, to the trees that border them and the animals that drink from them. Some lakes have seen the disappearance of all the aquatic species that inhabit them. In the United States, acid rain caused the erosion of limestone rocks which, by dissolving in rivers, caused the opposite extreme: the pH of the water increased and made it difficult to convert it into drinking water.
Regards
Thank you very much for your answer Bachir Achour, Anoop Kumar Srivastava, Kien Vu
There are those who believe that the interaction of carbon dioxide with water vapor will cause alkaline rain, while others say that it will fall acid rain. So what is the correct scientific opinion?
Dear Salam:
During the rain, water vapour condenses into droplets dissolving some carbon dioxide from the atmosphere (atmosphere has 0.04% CO2). It results in a dilute solution of carbonic acid H2CO3, which dissociates in water according to the following equilibrium reactions, as a weak acid:
H2CO3 HCO3- + H+
HCO3- CO3- - + H+
According to the above equilibrium, it can ONLY form H+ ions, but not OH- ions. So, the atmospheric CO2 can only contribute to ACID rain, but not ALKALINE rain. Similarly, if present, SO2 can do the same.
Although it is not very common, if you have aerosol dust particles such as CaCO3, it is theoretically possible to have an alkaline rain. However, unlike the acid rain, any alkalinity of soil or a body of water mainly originates from what is already present in the soil (such as CaCO3).
Regards,
Nimal
Can we say that alkaline rains are the best areas of their presence in dry areas?
It was believed in the past that acid rain, its origin is due to natural factors represented by the eruption of volcanoes, or as a result of natural fires that affect forests, or as a result of the process of decomposition of plants and animals.
But modern science has revealed that the main cause of acid rain is human activity, and studies have shown that 90% of the sulfur carried in rain is due to the smoke of factories and electric power stations, and as a result of burning coal and petroleum in large quantities, as they produce sulfur dioxide.
- Badges
- Science topic
- Similar topics
- Engineering
- Modeling