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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.
This is a list of minerals which have Wikipedia articles.. Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species.
Water has been found on the Sun, and there is evidence of H 2 in white dwarf stellar atmospheres. [2] [4] Cooler stars include absorption band spectra that are characteristic of molecules. Similar absorption bands can be found through observation of solar sun spots, which are cool enough to
The proportion of silica in rocks and minerals is a major factor in determining their names and properties. [7] Rock outcrop along a mountain creek near Orosí, Costa Rica. Rocks are classified according to characteristics such as mineral and chemical composition, permeability, texture of the constituent particles, and particle size.
Carbon can be produced in stars at least as massive as the Sun by fusion of three helium-4 nuclei: 4 He + 4 He + 4 He --> 12 C. This is the triple alpha process. In stars as massive as the Sun, carbon-12 is also converted to carbon-13 and then onto nitrogen-14 by fusion with protons. 12 C + 1 H --> 13 C + e +. 13 C + 1 H --> 14 N.
The second process, the carbon–nitrogen–oxygen cycle, which was also considered by Carl Friedrich von Weizsäcker in 1938, is more important in more massive main-sequence stars. [11]: 167 These works concerned the energy generation capable of keeping stars hot. A clear physical description of the proton–proton chain and of the CNO cycle ...
4 Rocks. 5 Chatoyant gems. 6 Asterism. 7 See also. ... There are a number of artificial and lab grown minerals used to produce gemstones. ... Eilat stone; Epidosite ...
Early mineralogy was determined by crystallization of igneous rocks and further bombardments. This phase was then replaced by extensive recycling of crust and mantle, so that at the end of this era there were about 1500 mineral species. However, few of the rocks survived from this period so the timing of many events remains uncertain. [1]