Search results
Results From The WOW.Com Content Network
Unprocessed phosphate rock has a concentration of 1.7–8.7% phosphorus by mass (4–20% phosphorus pentoxide). By comparison, the Earth's crust contains 0.1% phosphorus by mass, [84] and vegetation 0.03–0.2%. [85] Although quadrillions of tons of phosphorus exist in the Earth's crust, [86] these are currently not economically extractable.
The phosphate ion has a molar mass of 94.97 g/mol, and consists of a central phosphorus atom surrounded by four oxygen atoms in a tetrahedral arrangement. It is the conjugate base of the hydrogen phosphate ion H(PO 4) 2−, which in turn is the conjugate base of the dihydrogen phosphate ion H 2 (PO 4) −
Phosphorus; Pronunciation / ˈ f ɒ s f ər ə s / (FOS-fər-əs) Allotropes: white, red, violet, black and others (see Allotropes of phosphorus) Appearance: white, red and violet are waxy, black is metallic-looking: Standard atomic weight A r °(P)
The molar mass of atoms of an element is given by the relative atomic mass of the element multiplied by the molar mass constant, M u ≈ 1.000 000 × 10 −3 kg/mol ≈ 1 g/mol. For normal samples from Earth with typical isotope composition, the atomic weight can be approximated by the standard atomic weight [ 2 ] or the conventional atomic weight.
Dumas used the method to determine the vapour densities of elements (mercury, phosphorus, sulfur) and inorganic compounds. [3] Today, modern methods such as mass spectrometry and elemental analysis are used to determine the molecular weight of a substance.
Unlike nitrogen, its lighter pnictogen neighbor which forms a stable N 2 molecule with a nitrogen to nitrogen triple bond, phosphorus prefers a tetrahedral form P 4 because P-P pi-bonds are high in energy. Diphosphorus is, therefore, very reactive with a bond-dissociation energy (117 kcal/mol or 490 kJ/mol) half that of dinitrogen. The bond ...
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 molar mass constant, usually denoted by M u, is a physical constant defined as one twelfth of the molar mass of carbon-12: M u = M(12 C)/12. [1] The molar mass of an element or compound is its relative atomic mass (atomic weight) or relative molecular mass (molecular weight or formula weight) multiplied by the molar mass constant.