The most abundant gas on the planet is nitrogen, which occupies about four-fifths of the Earth's atmosphere. This element was isolated and recognized as a specific substance during the first air investigations.
Carl Wilhelm Scheele, a Swedish chemist, showed in 1772 that air is a mixture of two gases, one of which he called "fire air" (oxygen), because it supported combustion and the other "dirty air" (nitrogen), because it was what was left after the "fire air" had been exhausted.
At around the same time, nitrogen was also recognized by a Scottish botanist, Daniel Rutherford (who was the first to publish his findings), by British chemist Henry Cavendish, and by British clergyman and scientist Joseph Priestley, who together with Scheele, obtained recognition for the discovery of oxygen (Sanderson, 2017).
What gases make up the planet's atmosphere?
The atmosphere is made up of a mixture of several different gases, in different amounts. The permanent gases whose percentages do not change from day to day are; nitrogen, oxygen and argon.
Nitrogen represents 78% of the atmosphere, oxygen 21% and argon 0.9%. Gases such as carbon dioxide, nitrous oxides, methane, and ozone are waste gases that make up about one-tenth of one percent of the atmosphere (NC Estate University, 2013).
So we guess that nitrogen and oxygen make up about 99% of the gases in the atmosphere.
The remaining gases, such as carbon dioxide, water vapor, and noble gases like argon, are found in much smaller proportions (BBC, 2014).
Water vapor is the only one whose concentration varies from 0-4% of the atmosphere depending on where it is and the time of day.
In cold and dry arid regions, water vapor typically represents less than 1% of the atmosphere, while in humid tropical regions water vapor can account for almost 4% of the atmosphere. The water vapor content is very important in predicting the weather.
Greenhouse gases, whose percentages vary daily, seasonally and annually, have physical and chemical properties that make them interact with solar radiation and infrared light (heat) released from the Earth, to affect the energy balance of the globe.
This is the reason why scientists are closely monitoring the observed increase in greenhouse gases such as carbon dioxide and methane, as although they are small in quantity, they can strongly affect the global energy balance and temperature throughout. over time (NASA, SF).
Nitrogen gas
Nitrogen is essential for life on Earth, as it is a compound component of all proteins and can be found in all living systems.
Nitrogen compounds are present in organic materials, food, fertilizers, explosives, and poisons. Nitrogen is crucial for life, but in excess it can also be harmful to the environment.
Named after the Greek word nitron, meaning "native soda," and gene, meaning "to form," nitrogen is the fifth most abundant element in the universe.
As mentioned, nitrogen gas constitutes 78 percent of the Earth's air, according to the Los Alamos National Laboratory, California, USA On the other hand, the atmosphere of Mars is only 2.6 percent nitrogen.
The structure of the nitrogen molecule has a triple bond. This makes it very difficult to break down and gives it a certain inert gas character.
It is common for chemists to work in nitrogen-saturated atmospheres to obtain low-reactivity conditions (Royal Society of Chemistry, 2017).
Cycle of nitrogen
Nitrogen, like water and carbon, is a renewable natural resource which is replaced through the nitrogen cycle.
The nitrogen cycle, in which atmospheric nitrogen is converted into different organic compounds, is one of the most crucial natural processes for sustaining living organisms.
During the cycle, bacteria in the soil process or "fix" atmospheric nitrogen into ammonia, which plants need to grow.
Other bacteria convert ammonia into amino acids and proteins. So the animals eat the plants and consume the protein.
Nitrogen compounds return to the soil through animal waste. The bacteria convert the residual nitrogen into nitrogen gas, which returns to the atmosphere.
Nitrogen cycle
In an effort to make crops grow faster, people use nitrogen in fertilizers.
However, the excessive use of these fertilizers in agriculture has had devastating consequences for the environment and human health, as it has contributed to the contamination of ground and surface waters.
According to the United States Environmental Protection Agency (EPA), nutrient pollution caused by excess nitrogen and phosphorus in air and water is one of the most widespread, costly, and challenging environmental problems (Blaszczak-Boxe, 2014).
Nitrogen compounds are a primary component in the formation of ozone at ground level. In addition to causing respiratory problems, nitrogen compounds in the atmosphere contribute to the formation of acid rain (Oblack, 2016).
References
- (2014). The Earth's atmosphere. Recovered from bbc.co.uk.
- Blaszczak-Boxe, A. (2014, December 22). Facts About Nitrogen. Recovered from livescience.com.
- (SF). Atmospheric Composition. Recovered from science.nasa.gov.
- NC Estate University. (2013, August 9). Composition of the Atmosphere. Recovered from ncsu.edu.
- Oblack, R. (2016, February 3). Nitrogen - Gases in the Atmosphere. Recovered from thoughtco.com.
- Royal Society of Chemistry. (2017). Nitrogen. Recovered from rsc.org.
- Sanderson, RT (2017, February 12). Nitrogen (N). Recovered from britannica.com.