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The sites occupied solely by phosphate anions in stoichiometric hydroxyapatite, are occupied by phosphate or hydrogen phosphate, HPO 2− 4, anions. [14] Preparation of these calcium-deficient phases can be prepared by precipitation from a mixture of calcium nitrate and diammonium phosphate with the desired Ca/P ratio, for example, to make a ...
Calcium phosphate is the usual constitution of microcalcifications of the breast, particularly dystrophic calcifications. Microcalcifications as can be seen on mammography can be an early sign of breast cancer. Based on morphology, it is possible to classify by radiography how likely microcalcifications are to indicate cancer. [7]
Dicalcium phosphate is the calcium phosphate with the formula CaHPO 4 and its dihydrate. The "di" prefix in the common name arises because the formation of the HPO 42– anion involves the removal of two protons from phosphoric acid, H 3 PO 4. It is also known as dibasic calcium phosphate or calcium monohydrogen phosphate.
About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium. All 11 are necessary for life. The remaining elements are trace elements, of which more than a dozen are ...
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) −
The single-bonded oxygen atoms that are not shared are completed with acidic hydrogen atoms. The general formula of a phosphoric acid is Hn+2−2xPnO3n+1−x, where n is the number of phosphorus atoms and x is the number of fundamental cycles in the molecule's structure, between 0 and n + 2 2 . Pyrophosphate anion. Trimethyl orthophosphate.
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Calcium hydroxyphosphate (calcium phosphate tribasic, tribasic calcium phosphate, hydroxyapatite, HAp) is an inorganic chemical compound that is made up of calcium, hydrogen, oxygen and phosphorus. Its formula is Ca 5 (OH) (PO 4) 3.
Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and ...