Calcium carbonateCalcium carbonate is a chemical compound with the chemical formula . It is a common substance found in rocks as the minerals calcite and aragonite, most notably in chalk and limestone, eggshells, gastropod shells, shellfish skeletons and pearls. Materials containing much calcium carbonate or resembling it are described as calcareous. Calcium carbonate is the active ingredient in agricultural lime and is created when calcium ions in hard water react with carbonate ions to create limescale.
Organic chemistryOrganic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms. Study of structure determines their structural formula. Study of properties includes physical and chemical properties, and evaluation of chemical reactivity to understand their behavior.
Carbonate mineralCarbonate minerals are those minerals containing the carbonate ion, CO32-. Calcite group: trigonal Calcite CaCO3 Gaspéite (Ni,Mg,Fe2+)CO3 Magnesite MgCO3 Otavite CdCO3 Rhodochrosite MnCO3 Siderite FeCO3 Smithsonite ZnCO3 Spherocobaltite CoCO3 Aragonite group: orthorhombic Aragonite CaCO3 Cerussite PbCO3 Strontianite SrCO3 Witherite BaCO3 Rutherfordine UO2CO3 Natrite Na2CO3 Dolomite group: trigonal Ankerite CaFe(CO3)2 Dolomite CaMg(CO3)2 Huntite Mg3Ca(CO3)4 Minrecordite CaZn(CO3)2 Barytocalcite BaCa(CO3)2 Carbonate with hydroxide: monoclinic Azurite Cu3(CO3)2(OH)2 Hydrocerussite Pb3(CO3)2(OH)2 Malachite Cu2CO3(OH)2 Rosasite (Cu,Zn)2CO3(OH)2 Phosgenite Pb2(CO3)Cl2 Hydrozincite Zn5(CO3)2(OH)6 Aurichalcite (Zn,Cu)5(CO3)2(OH)6 Hydromagnesite Mg5(CO3)4(OH)2.
Magnesium carbonateMagnesium carbonate, (archaic name magnesia alba), is an inorganic salt that is a colourless or white solid. Several hydrated and basic forms of magnesium carbonate also exist as minerals. The most common magnesium carbonate forms are the anhydrous salt called magnesite (), and the di, tri, and pentahydrates known as barringtonite (), nesquehonite (), and lansfordite (), respectively. Some basic forms such as artinite (), hydromagnesite (), and dypingite () also occur as minerals. All of those minerals are colourless or white.
Mechanism (philosophy)Mechanism is the belief that natural wholes (principally living things) are similar to complicated machines or artifacts, composed of parts lacking any intrinsic relationship to each other. The doctrine of mechanism in philosophy comes in two different flavors. They are both doctrines of metaphysics, but they are different in scope and ambitions: the first is a global doctrine about nature; the second is a local doctrine about humans and their minds, which is hotly contested.
Euler's constantEuler's constant (sometimes called the Euler–Mascheroni constant) is a mathematical constant, usually denoted by the lowercase Greek letter gamma (γ), defined as the limiting difference between the harmonic series and the natural logarithm, denoted here by log: Here, ⌊ ⌋ represents the floor function. The numerical value of Euler's constant, to 50 decimal places, is: The constant first appeared in a 1734 paper by the Swiss mathematician Leonhard Euler, titled De Progressionibus harmonicis observationes (Eneström Index 43).
ReductionismReductionism is any of several related philosophical ideas regarding the associations between phenomena which can be described in terms of other simpler or more fundamental phenomena. It is also described as an intellectual and philosophical position that interprets a complex system as the sum of its parts. The Oxford Companion to Philosophy suggests that reductionism is "one of the most used and abused terms in the philosophical lexicon" and suggests a three-part division: Ontological reductionism: a belief that the whole of reality consists of a minimal number of parts.
PurpuraPurpura (ˈpɜːrpjʊərə) is a condition of red or purple discolored spots on the skin that do not blanch on applying pressure. The spots are caused by bleeding underneath the skin secondary to platelet disorders, vascular disorders, coagulation disorders, or other causes. They measure 3–10 mm, whereas petechiae measure less than 3 mm, and ecchymoses greater than 1 cm. Purpura is common with typhus and can be present with meningitis caused by meningococci or septicaemia.
VitalismVitalism is a belief that starts from the premise that "living organisms are fundamentally different from non-living entities because they contain some non-physical element or are governed by different principles than are inanimate things." Where vitalism explicitly invokes a vital principle, that element is often referred to as the "vital spark", "energy", "élan vital" (coined by vitalist Henri Bergson), "vital force", or "vis vitalis", which some equate with the soul.