However, nitrogen compounds are found in foods, organic materials, fertilizers, poisons, and explosives. Nitrogen, as a gas is colorless, odorless, and generally considered an inert element. Nitrogen gas can be prepared by heating a water solution of ammonium nitrite NH 4 NO 3.
Sodium nitrate NaNO 3 and potassium nitrate KNO 3 are formed by the decomposition of organic matter with compounds of these metals present. In certain dry areas of the world these saltpeters are found in quantity and are used as fertilizers. The nitrogen cycle is one of the most important processes in nature for living organisms. In other words, Nature has provided a method to produce nitrogen for plants to grow.
Animals eat the plant material where the nitrogen has been incorporated into their system, primarily as protein. The cycle is completed when other bacteria convert the waste nitrogen compounds back to nitrogen gas. Nitrogen is crucial to life, as it is a component of all proteins. Ammonia NH 3 is the most important commercial compound of nitrogen. Hydrogen was more carefully prepared and collected by the brilliant but reclusive millionaire scientist Henry Cavendish about a years later. Cavendish called the gas inflammable air from the metals in recognition of this most striking property.
He also studied the gas we know call carbon dioxide, which had first been prepared by the Scottish chemist, Joseph Black in the s. Black called carbon dioxide fixed air, since it was thought to be locked up or fixed in certain minerals such as limestone. It could be released from its stony prison by the action of heat or acids. Carbon dioxide was also known by the name mephitic air the word mephitic meaning noxious or poisonous. This name obviously came from its property of destroying life, since it rapidly suffocates any animals immersed in it.
This is where the confusion with nitrogen gas begins, since pure nitrogen gas is also suffocating to animals. If the oxygen in an enclosed quantity of air is used up, either by burning a candle in it or by confining an animal, most of the oxygen is converted to carbon dioxide gas which mixes with the nitrogen gas present in the air.
This noxious mixture no longer supports life and so was called mephitic. The crucial experiment in the discovery of nitrogen was when it was realized that there are at least two different kinds of suffocating gases in this mephitic air.
This was done by passing the mixture of gases through a solution of alkali, which absorbed the carbon dioxide but left behind the nitrogen gas. Cavendish prepared nitrogen gas by this means.
He passed air back and forth over heated charcoal which converted the oxygen in the air to carbon dioxide. The carbon dioxide was then dissolved in alkali leaving behind the inert nitrogen gas, which he correctly observed was slightly less dense than common air.
Unfortunately, Cavendish didn't publish his findings. He just communicated them in a letter to fellow scientist, Joseph Priestley, one of the discoverers of oxygen gas. Consequently, the discovery of nitrogen is usually accredited to one of Joseph Black's students, the Scottish scientist, Daniel Rutherford, who's also the uncle of the novelist and poet, Sir Walter Scott. Rutherford published his findings, which was similar to those of Cavendish in his doctoral thesis entitled, "An Inaugural Dissertation on the Air called Fixed or Mephitic" in So what about the name, nitrogen?
In the late s, chemical nomenclature underwent a major revolution under the guidance of the French chemist, Antoine Lavoisier. It was he and his colleagues, who suggested many of the names we still use today including the word hydrogen, which comes from the Greek meaning water former and oxygen from the Greek for acid producer, since Lavoisier mistakenly thought that oxygen was the key component of all acids.
However, in his list of the then known elements, Lavoisier included the term azote or azotic gas for what we now call nitrogen. This again stems from Greek words, this time meaning the absence of life, once again focussing on its mephitic quality. It was not long before it was pointed out that there are many mephitic gases, in fact no gas other than oxygen can support life.
The name nitrogen was therefore proposed from the observation, again first made by Cavendish that if the gases sparked with oxygen, and then the resulting nitrogen dioxide gases passed through alkali, nitre, otherwise known as saltpetre or potassium nitrate is formed.
The word nitrogen therefore means nitre former. The derivatives of the word, azote still survive today. The compound used to explosively fill car air bags with gas is sodium azide, a compound of just sodium and nitrogen.
When triggered this compound explosively decomposes freeing the nitrogen gas, which inflates the bags. Far from destroying life, this azotic compound has been responsible for saving thousands.
Cambridge University's Peter Wothers telling the story of the discovery of nitrogen. Next time on Chemistry in its element, how chemists like Mendeleev got to grips with both the known and the unknown.
While other scientists had tried to create ways of ordering the known elements, Mendeleev created the system that could predict the existence of elements, not yet discovered. When he presented the table to the world in , it contained four prominent gaps. One of these was just below manganese and Mendeleev predicted that element with atomic weight 43 would be found to fill that gap, but it was not until that a group of Italian scientists finally found the missing element, which they named technetium.
And you can hear Mark Peplow telling technetium's tale in next week's edition of Chemistry in its element. I'm Chris Smith, thank you for listening. See you next time. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld. Click here to view videos about Nitrogen.
View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists.
Download our free Periodic Table app for mobile phones and tablets. Explore all elements. D Dysprosium Dubnium Darmstadtium.
E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium. G Gallium Germanium Gadolinium Gold. I Iron Indium Iodine Iridium. K Krypton. O Oxygen Osmium Oganesson. U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium. Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership. Facebook Twitter LinkedIn Youtube. Discovery date. Discovered by.
Daniel Rutherford. Origin of the name. The name is derived from the Greek 'nitron' and 'genes' meaning nitre forming. Melting point. Boiling point. Atomic number. Relative atomic mass. Key isotopes. Electron configuration. CAS number. Named after the Greek word nitron , for "native soda," and genes for "forming," nitrogen is the fifth most abundant element in the universe.
On the other hand, the atmosphere of Mars is only 2. In its gas form, nitrogen is colorless, odorless and generally considered as inert. In its liquid form, nitrogen is also colorless and odorless, and looks similar to water, according to Los Alamos.
Nitrogen was discovered in by chemist and physician Daniel Rutherford, when he removed oxygen and carbon dioxide from air, demonstrating that the residual gas would not support living organisms or combustion, according to the Los Alamos National Laboratory.
Other scientists, including Carl Wilhelm Scheele and Joseph Priestly, were working on the same problem, and called nitrogen "burnt" air, or air without oxygen.
In , Antoine Laurent de Lavoisier, called nitrogen "azote," which means "lifeless. One of the most important nitrogen compounds is ammonia NH 3 , which can be produced in the so-called Haber-Bosch process, in which nitrogen is reacted with hydrogen. The colorless ammonia gas with a pungent smell can be easily liquefied into a nitrogen fertilizer. In fact, about 80 percent of ammonia that is produced is used as fertilizer.
It is also used as a refrigerant gas; in the manufacture of plastics, textiles, pesticides and dyes; and in cleaning solutions, according to the New York Department of State. The nitrogen cycle, in which atmospheric nitrogen is converted into different organic compounds, is one the most crucial natural processes to sustain living organisms.
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