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Calcium oxide (formula: Ca O), commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic , alkaline , crystalline solid at room temperature . The broadly used term lime connotes calcium-containing inorganic compounds , in which carbonates , oxides , and hydroxides of calcium, silicon , magnesium ...
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
Particles finer than 0.1 μm (10 −7 m) in water remain continuously in motion due to electrostatic charge (often negative) which causes them to repel each other. [citation needed] Once their electrostatic charge is neutralized by the use of a coagulant chemical, the finer particles start to collide and agglomerate (collect together) under the influence of Van der Waals forces.
Ettringite is the most common and prominent member of the AFt group (X in this case denoting sulfate), and often simply called Alumina Ferrite tri-sulfate (AFt). AFm: abbreviation for "alumina, ferric oxide, mono-substituted" or (Al 2 O 3 − Fe 2 O 3 − mono). It represents another group of calcium aluminate hydrates with general formula [Ca ...
Aluminium sulfate is a salt with the formula Al 2 (SO 4) 3. It is soluble in water and is mainly used as a coagulating agent (promoting particle collision by neutralizing charge) in the purification of drinking water [ 3 ] [ 4 ] and wastewater treatment plants , and also in paper manufacturing.
About 2.2:1 is the ratio (by weight) for compounding sulfur and quicklime; this makes the highest proportion of calcium pentasulfide. If calcium hydroxide (builders or hydrated lime) is used, an increase by 1/3 or more (to 115 g/L or more) might be used with the 192 g/L of sulfur. If the quicklime is 85%, 90%, or 95% pure, use 101 g/L, 96 g/L ...
The root of the word calcination refers to its most prominent use, which is to remove carbon from limestone (calcium carbonate) through combustion to yield calcium oxide (quicklime). This calcination reaction is CaCO 3 (s) → CaO(s) + CO 2 (g). Calcium oxide is a crucial ingredient in modern cement, and is also used as a chemical flux in smelting.
AFm form inter alia when tricalcium aluminate 3CaO·Al 2 O 3, or C 3 A in CCN, reacts with dissolved calcium sulfate (CaSO 4), or calcium carbonate (CaCO 3). As the sulfate form is the dominant one in AFm phases in the hardened cement paste (HCP) in concrete, AFm is often simply referred to as Aluminate Ferrite monosulfate or calcium aluminate ...