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Although most compounds are referred to by their IUPAC systematic names (following IUPAC nomenclature), traditional names have also been kept where they are in wide use or of significant historical interests.
These baryons (protons, neutrons, hyperons, etc.) which comprise the nucleus are called nucleons. Each type of nucleus is called a "nuclide", and each nuclide is defined by the specific number of each type of nucleon. "Isotopes" are nuclides which have the same number of protons but differing numbers of neutrons.
This is an index of lists of molecules (i.e. by year, number of atoms, etc.). Millions of molecules have existed in the universe since before the formation of Earth. Three of them, carbon dioxide, water and oxygen were necessary for the growth of life.
Nitrogen-13 and oxygen-15 are produced in the atmosphere when gamma rays (for example from lightning) knock neutrons out of nitrogen-14 and oxygen-16: 14 N + γ → 13 N + n 16 O + γ → 15 O + n. The nitrogen-13 produced as a result decays with a half-life of 9.965(4) min to carbon-13, emitting a positron.
Stable even–even nuclides number as many as three isobars for some mass numbers, and up to seven isotopes for some atomic numbers. Conversely, of the 251 known stable nuclides, only five have both an odd number of protons and odd number of neutrons: hydrogen-2 , lithium-6, boron-10, nitrogen-14, and tantalum-180m.
14 N is one of the five stable odd–odd nuclides (a nuclide having an odd number of protons and neutrons); the other four are 2 H, 6 Li, 10 B, and 180m Ta. [ 34 ] The relative abundance of 14 N and 15 N is practically constant in the atmosphere but can vary elsewhere, due to natural isotopic fractionation from biological redox reactions and ...
For nitrogen, the +5 state is typically serves as only a formal explanation of molecules like N 2 O 5, as the high electronegativity of nitrogen causes the electrons to be shared almost evenly. [clarification needed] Pnictogen compounds with coordination number 5 are hypervalent. Nitrogen(V) fluoride is only theoretical and has not been ...
There are a number of exceptions and special cases that violate the above rules. Sometimes the prefix is left off the initial atom: I 2 O 5 is known as iodine pentaoxide, but it should be called diiodine pentaoxide. N 2 O 3 is called nitrogen sesquioxide (sesqui-means 1 + 1 ⁄ 2). The main oxide of phosphorus is called phosphorus pentaoxide.