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Pie charts of typical human body composition by percent of mass, and by percent of atomic composition (atomic percent) Body composition may be analyzed in various ways. This can be done in terms of the chemical elements present, or by molecular structure e.g., water , protein , fats (or lipids ), hydroxyapatite (in bones), carbohydrates (such ...
Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other' and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.
Lonsdaleite is an allotrope sometimes called "hexagonal diamond", formed from graphite present in meteorites upon their impact on the earth. The great heat and pressure of the impact transforms the graphite into a denser form similar to diamond but retaining graphite's hexagonal crystal lattice. "Hexagonal diamond" has also been synthesized in ...
Biomolecules are an important element of living organisms. They are often endogenous, [2] i.e. produced within the organism, [3] but organisms usually also need exogenous biomolecules, for example certain nutrients, to survive. Biomolecules and their reactions are studied in biology and its subfields of biochemistry and molecular biology.
White phosphorus, yellow phosphorus, or simply tetraphosphorus (P 4) is an allotrope of phosphorus.It is a translucent waxy solid that quickly yellows in light (due to its photochemical conversion into red phosphorus), [2] and impure white phosphorus is for this reason called yellow phosphorus.
The diphosphorus allotrope (P 2) can normally be obtained only under extreme conditions (for example, from P 4 at 1100 kelvin). In 2006, the diatomic molecule was generated in homogeneous solution under normal conditions with the use of transition metal complexes (for example, tungsten and niobium). [41]
These can be inorganic (for example, water and metal ions) or organic (for example, the amino acids, which are used to synthesize proteins). [7] The mechanisms used by cells to harness energy from their environment via chemical reactions are known as metabolism. The findings of biochemistry are applied primarily in medicine, nutrition, and ...
This soft, brittle allotrope of arsenic has a steel gray, metallic color, and is a good conductor. [2] The rhombohedral form of this allotrope is analogous to the phosphorus allotrope black phosphorus. In its α-form, As 6 rings in chair confirmations are condensed into packed layers lying perpendicular to the crystallographic c axis. Within ...