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Nitrogen, nonmetallic element of Group 15 [Va] of the periodic table. It is a colorless, odorless, tasteless gas that is the most plentiful element in Earth’s atmosphere and is a constituent of all living matter. Its atomic number is 7 and it is denoted by the symbol ‘N’ in the periodic table.
Nitrogen - Properties, Reactions, Compounds: Nitrogen is a colourless, odourless gas, which condenses at −195.8 °C to a colourless, mobile liquid. The element exists as N2 molecules, represented as :N:::N:, for which the bond energy of 226 kilocalories per mole is exceeded only by that of carbon monoxide, 256 kilocalories per mole.
Nitrogen - Compounds, Reactions, Uses: Although the other applications are important, by far the greatest bulk of elemental nitrogen is consumed in the manufacture of nitrogen compounds. The triple bond between atoms in the nitrogen molecules is so strong (226 kilocalories per mole, more than twice that of molecular hydrogen) that it is ...
nitrogen group element, any of the chemical elements that constitute Group 15 (Va) of the periodic table. The group consists of nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), and moscovium (Mc).
Pyrrole, furan, and thiophene molecules each contain five-membered rings, composed of four atoms of carbon and one atom of nitrogen, oxygen, or sulfur, respectively. Pyridine and pyrrole are both nitrogen heterocycles—their molecules contain nitrogen atoms along with carbon atoms in the rings.
An example of an atom of the first type is the nitrogen atom in pyrrole, which is linked by single covalent bonds to two carbon atoms and one hydrogen atom. Nitrogen has an outermost shell of five electrons, three of which can enter into three covalent bonds with other atoms.
Nitrogen group element - Bonding Capacity, Variations, Properties: Significant differences in electronic configurations also occur among the elements of the nitrogen group with respect both to the underlying shell and to the outer d orbitals.
Seven-membered heterocycles with one or two nitrogen atoms in the ring are structural units of widely used psychopharmaceuticals such as imipramine (trade name Prazepine)—the first of the tricyclic antidepressants—and the tranquilizer diazepam (trade name Valium).
Atomic model, in physics, a model used to describe the structure and makeup of an atom. Atomic models have gone through many changes over time, evolving as necessary to fit experimental data. For a more in-depth discussion of the history of atomic models, see atom: development of atomic theory.
Alkaloid, any of a class of naturally occurring organic nitrogen-containing bases. Alkaloids have diverse and important physiological effects on humans and other animals. Well-known alkaloids include morphine, strychnine, quinine, ephedrine, and nicotine.