10 Interesting Facts About Nitrogen

You breathe oxygen, yet the air we inhale is mostly nitrogen. You need nitrogen to live and encounter it in the foods you eat and in many common chemicals. Here are some quick facts and detailed information about this crucially important element.

1. Nitrogen is atomic number 7, which means each nitrogen atom has 7 protons. Its element symbol is N. Nitrogen is odorless, tasteless, and colorless gas at room temperature and pressure. Its atomic weight is 14.0067.
2. Nitrogen gas (N₂) makes up 78.1% of the volume of the Earth's air. It's the most common uncombined (pure) element on Earth. It's estimated to be the 5th or 7th most abundant element in the Solar System and Milky Way (present in much lower amounts than hydrogen, helium, and oxygen, so it's hard to get a hard figure). While the gas is common on Earth, it's not so abundant on other planets. For example, nitrogen gas is found in the atmosphere of Mars at levels of about 2.6 percent.
3. Nitrogen is a nonmetal. Like other elements in this group, it is a poor conductor of heat and electricity and lacks metallic luster in solid form.
4. Nitrogen gas is relatively inert, but soil bacteria can 'fix' nitrogen into a form that plants and animals can use to make amino acids and proteins.
5. The French chemist Antoine Laurent Lavoisier named nitrogen azote, meaning "without life". The name became nitrogen, which derives from the Greek word nitron, which means "native soda" and genes, which means "forming". Credit for the discovery of the element is generally given to Daniel Rutherford, who found it could be separated from air in 1772.
6. Nitrogen was sometimes referred to as "burnt" or "dephlogisticated" air, since air that no longer contains oxygen is almost all nitrogen. The other gases in air are present in much lower concentrations.
7. Nitrogen compounds are found in foods, fertilizers, poisons, and explosives. Your body is 3% nitrogen by weight. All living organisms contain this element.
8. Nitrogen is responsible for the orange-red, blue-green, blue-violet, and deep violet colors of the aurora.
9. One way to prepare nitrogen gas is by liquefaction and fractional distillation from the atmosphere. Liquid nitrogen boils at 77 K (−196 °C, −321 °F). Nitrogen freezes at 63 K (-210.01 °C).
10. Liquid nitrogen is a cryogenic fluid, capable of freezing skin on contact. While the Leidenfrost effect protects skin from very brief exposure (less than one second), ingesting liquid nitrogen can cause severe injury. When liquid nitrogen is used to make ice cream, the nitrogen vaporizes. However, the liquid nitrogen is used to produce fog in cocktails, there is a real danger of ingesting the liquid. Damage occurs from pressure generated by expanding gas as well as from the cold temperature.
11. Nitrogen has a valence of 3 or 5. It forms negatively charged ions (anions) that readily react with other nonmetals to form covalent bonds.
12. Saturn's largest moon, Titan, is the only moon in the solar system with a dense atmosphere. Its atmosphere consists of over 98% nitrogen.
13. Nitrogen gas is used as a nonflammable protective atmosphere. The liquid form of the element is used to remove warts, as a computer coolant, and for cryogenics. Nitrogen is part of many important compounds, such as nitrous oxide, nitroglycerin, nitric acid, and ammonia. The triple bond nitrogen forms with other nitrogen atoms is extremely strong and releases considerable energy when broken, which is why it is so valuable in explosives and also "strong" materials such as Kevlar and cyanoacrylate glue ("super glue").
14. Decompression sickness, commonly known as "the bends", occurs when reduced pressure causing nitrogen gas bubbles to form in the bloodstream and organs.

Sources

• Liquid nitrogen cocktail leaves teen in hospital, BBC News, October 8, 2012. 
• Meija, J.; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91.
• "Neptune: Moons: Triton". NASA. Archived from the original on October 5, 2011. Retrieved March 3, 2018.
• Priestley, Joseph (1772). "Observations on different kinds of air". Philosophical Transactions of the Royal Society of London. 62: 147–256. 
• Weeks, Mary Elvira (1932). "The discovery of the elements. IV. Three important gases". Journal of Chemical Education. 9 (2): 215.