Nitrogen compounds were well known during the Middle Ages. Alchemists knew nitric acid as aqua fortis strong water. The mixture of nitric and hydrochloric acids was known as aqua regia royal water , celebrated for its ability to dissolve gold the king of metals.
The earliest military, industrial, and agricultural applications of nitrogen compounds used saltpetre sodium nitrate or potassium nitrate , most notably in gunpowder and later as fertilizer. Nitrogen is a chemical element with symbol N and atomic number 7. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting Nitrogen is a common element in the universe, estimated at about seventh in total abundance in our galaxy and the solar system.
Its occurrence there is thought to be entirely due to synthesis by fusion of carbon and hydrogen in supernovas. Due to the volatility of elemental nitrogen and its compounds with hydrogen and oxygen, nitrogen is far less common on the rocky planets of the inner solar system and is a relatively rare element on Earth. However, as on Earth, nitrogen and its compounds occur commonly as gases in the atmospheres of planets and moons.
Nitrogen occurs in all living organisms, primarily in amino acids which make up proteins, and nucleic acids DNA and RNA. Nitrogen is found in a wide variety of organic compounds. Compounds which contain carbon-nitrogen single bonds are called amines , and may be thought of as organic derivatives of ammonia with carbon groups replacing the hydrogen atoms.
Amines are weakly basic, and are present in many pharmaceutical compounds, often referred to as alkaloids because of their basicity. If the nitrogen is connected to a carbon which is double-bonded to an oxygen atom, the functional group is called an amide ; amino acids are connected together to form proteins by amide linkages. Carbon-nitrogen double bonds, called imines , are also very common.
Nitrogen is incorporated into a large number of organic compounds of tremendous biological importance, such as the amino acids, nucleic acids, ATP, proteins, DNA, RNA, etc. Green plants contain a molecule called chlorophyll , which consists of a flat ring of carbon and nitrogen atoms with a large open space in the middle, in which a magnesium ion is bound, held in place by the nitrogen atoms.
The hemoglobin molecule contains a similar ring structure, which an iron ion bound in the cavity; this molecule is incorporated into a protein called hemoglobin, which is responsible for transporting oxygen in the bloodstream.
Nitrogen forms many compounds with oxygen. One of the most important of these is nitric oxide, NO, also known as nitrogen monoxide, which is produced in the body from the amino acid arginine; it acts as a vasodilator, causing blood vessels to relax and increasing blood flow.
Some heart medications, such as nitroglycerin and amyl nitrate, increase the amount of nitric oxide in the blood, allowing the delivery of more blood to the heart during an episode of heart pain angina or heart attack. The drug Viagra works by a similar mechanism, except that the blood is delivered elsewhere. Nitric oxide also acts as a neurotransmitter. In the atmosphere, nitric oxide is a pollutant, produced in automobile exhaust and power plants; it can be converted into nitrogen dioxide and nitric acid, HNO 3 , which leads to increased acidity levels in rain.
Nitrous oxide, N 2 O, also known as dinitrogen monoxide or laughing gas, is a mild anesthetic used in dentistry and surgery; it is also used as an aerosol propellant in cans of whipped cream. Nitrogen dioxide, NO 2 , is produced in the exhaust from motor vehicles, and reacts with hydrocarbons in the air to produce photochemical smog.
Nitrogen is also found in a number of explosives. Gunpowder contains potassium nitrate, KNO 3 , also known as saltpeter, which is a powerful oxidizing agent; the other components of gunpowder are sulfur, and coal. Nitroglycerin is made from the molecule glycerin or glycerol , which is a chain of three carbon atoms, each of which has an OH group on it; in nitroglycerine, the H on the OH is replaced by the nitro group, NO 2. Nitroglycerin is dangerously unstable, but when mixed with kieselguhr diatomaceous earth , which acts as an adsorbent, it is safer to handle, and does not explode until set off by a smaller explosion from a detonator such as a blasting cap.
Dynamite was invented by the Swedish chemist Alfred Nobel in ; on his death, his fortune was used to establish the Nobel Prizes, which are awarded for outstanding achievements in the sciences, literature, and peace.
TNT 2,4,6-trinitrotoluene , is a benzene ring with a CH 3 group attached forming the toluene molecule to which three nitro groups are attached which is accomplished by the use of a mixture of concentrated nitric and sulfuric acids. TNT is stable for long periods of time, and is not shock sensitive as nitroglycerin is. Nitrogen is essential to life as it is necessary to the formation of amino acids, proteins and nucleic bases such as DNA and RNA.
What type of element is nitrogen? Chemistry Matter Elements. Jan 21, David Drayer. 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.
0コメント