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Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System.
A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]
Many other binary nitrogen hydrides are known, but the most important are hydrazine (N 2 H 4) and hydrogen azide (HN 3). Although it is not a nitrogen hydride, hydroxylamine (NH 2 OH) is similar in properties and structure to ammonia and hydrazine as well. Hydrazine is a fuming, colourless liquid that smells similarly to ammonia.
Graphic representation of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. CHNOPS and CHON are mnemonic acronyms for the most common elements in living organisms. . "CHON" stands for carbon, hydrogen, oxygen, and nitrogen, which together make up more than 95 percent of the mass of biological system
Nitrogen-15 is frequently used in NMR (Nitrogen-15 NMR spectroscopy). Unlike the more abundant nitrogen-14, which has an integer nuclear spin and thus a quadrupole moment, 15 N has a fractional nuclear spin of one-half, which offers advantages for NMR such as narrower line width. Nitrogen-15 tracing is a technique used to study the nitrogen cycle.
Purine is a heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together.It is water-soluble.Purine also gives its name to the wider class of molecules, purines, which include substituted purines and their tautomers.
Chitin is the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chitin are produced each year in the biosphere. [1] It is a primary component of cell walls in fungi (especially filamentous and mushroom-forming fungi), the exoskeletons of arthropods such as crustaceans and insects, the radulae ...
The carbon monoxide molecule (CO) is very similar to dinitrogen in size, and it can mix in all proportions with solid nitrogen without changing crystal structure. Carbon monoxide is also found on the surfaces of Pluto and Triton at levels below 1%. Variations in the infrared linewidth of carbon monoxide absorption can reveal the concentration.