Calcium carbide.

Calcium phosphide is often used in naval flares, as in contact with water it liberates phosphine which self-ignites in contact with air ; it is often used together with calcium carbide which releases acetylene.

* Calcium carbide, a chemical compound

Calcium carbide is also used for ripening fruit artificially in some countries.

Calcium carbide reacts with water to produce acetylene, which acts as an artificial ripening agent.

Calcium carbide is made in this way as it requires a large amount of energy to promote an endothermic reaction ( at temperatures of 2500 ° C ).

# REDIRECT Calcium carbide

Calcium ion ( Ca < sup >++</ sup >) antagonists ( Calcium channel blockers ) are used in the treatment of chronic stable angina.

Calcium is essential for living organisms, in particular in cell physiology, where movement of the calcium ion Ca < sup > 2 +</ sup > into and out of the cytoplasm functions as a signal for many cellular processes.

Calcium, with a density of 1. 55 g / cm < sup > 3 </ sup >, is the lightest of the alkaline earth metals ; magnesium ( specific gravity 1. 74 ) and beryllium ( 1. 84 ) are more dense, although lighter in atomic mass.

Calcium salts are colorless from any contribution of the calcium, and ionic solutions of calcium ( Ca < sup > 2 +</ sup >) are colorless as well.

Calcium carbonate ( CaCO < sub > 3 </ sub >) is one of the common compounds of calcium.

Calcium has four stable isotopes (< sup > 40 </ sup > Ca, < sup > 42 </ sup > Ca, < sup > 43 </ sup > Ca and < sup > 44 </ sup > Ca ), plus two more isotopes (< sup > 46 </ sup > Ca and < sup > 48 </ sup > Ca ) that have such long half-lives that for all practical purposes they also can be considered stable.

Calcium also has a cosmogenic isotope, radioactive < sup > 41 </ sup > Ca, which has a half-life of 103, 000 years.

* Calcium carbonate ( CaCO < sub > 3 </ sub >) is used in manufacturing cement and mortar, lime, limestone ( usually used in the steel industry ) and aids in production in the glass industry.

* Calcium arsenate ( Ca < sub > 3 </ sub >( AsO < sub > 4 </ sub >)< sub > 2 </ sub >) is used in insecticides.

* Calcium chloride ( CaCl < sub > 2 </ sub >) is used in ice removal and dust control on dirt roads, in conditioner for concrete, as an additive in canned tomatoes, and to provide body for automobile tires.

* Calcium cyclamate ( Ca ( C < sub > 6 </ sub > H < sub > 11 </ sub > NHSO < sub > 3 </ sub >)< sub > 2 </ sub >) was used as a sweetening agent but is no longer permitted for use because of suspected cancer-causing properties.

* Calcium gluconate ( Ca ( C < sub > 6 </ sub > H < sub > 11 </ sub > O < sub > 7 </ sub >)< sub > 2 </ sub >) is used as a food additive and in vitamin pills.

* Calcium permanganate ( Ca ( MnO < sub > 4 </ sub >)< sub > 2 </ sub >) is used in liquid rocket propellant, textile production, as a water sterilizing agent and in dental procedures.

* Calcium phosphate ( Ca < sub > 3 </ sub >( PO < sub > 4 </ sub >)< sub > 2 </ sub >) is used as a supplement for animal feed, fertilizer, in commercial production for dough and yeast products, in the manufacture of glass, and in dental products.

* Calcium hydroxide solution ( Ca ( OH )< sub > 2 </ sub >) ( also known as limewater ) is used to detect the presence of carbon dioxide by being bubbled through a solution.

* Calcium hypochlorite ( Ca ( OCl )< sub > 2 </ sub >) is used as a swimming pool disinfectant, as a bleaching agent, as an ingredient in deodorant, and in algaecide and fungicide.

* Calcium phosphide ( Ca < sub > 3 </ sub > P < sub > 2 </ sub >) is used in fireworks, rodenticide, torpedoes and flares.

* Calcium stearate ( Ca ( C < sub > 18 </ sub > H < sub > 35 </ sub > O < sub > 2 </ sub >)< sub > 2 </ sub >) is used in the manufacture of wax crayons, cements, certain kinds of plastics and cosmetics, as a food additive, in the production of water resistant materials and in the production of paints.

* Calcium sulfate ( CaSO < sub > 4 </ sub >· 2H < sub > 2 </ sub > O ) is used as common blackboard chalk, as well as, in its hemihydrate form better known as Plaster of Paris.

Calcium sulfoaluminate cements are made from clinkers that include ye ' elimite ( Ca < sub > 4 </ sub >( AlO < sub > 2 </ sub >)< sub > 6 </ sub > SO < sub > 4 </ sub > or C < sub > 4 </ sub > A < sub > 3 </ sub > in Cement chemist's notation ) as a primary phase.

* Calcium Ca < sup > 2 +</ sup >

Calcium to phosphorus ratios should be 2: 1 to prevent hypocalcemia, sometimes known as hind leg paralysis ( HLP ).

Calcium released by basalts binds up CO < sub > 2 </ sub > from the atmosphere forming CaCO < sub > 3 </ sub > acting thus as a CO < sub > 2 </ sub > trap.

When the cement paste exposed to the air and meteoric water reacts with the atmospheric CO < sub > 2 </ sub >, portlandite and the Calcium Silicate Hydrate ( CSH ) of the hardened cement paste become progressively carbonated and the high pH gradually decreases from 13. 5 – 12. 5 to 8. 5, the pH of water in equilibrium with calcite ( calcium carbonate ) and the steel is no longer passivated.

** Calcium < 2 mmol / L

* Calcium < 2 mmol / L

Calcium ( Ca ) is in group 2, for it contains 2 valence electrons.

* Calcium tungstate ( CaWO < sub > 4 </ sub >) is used in luminous paints, fluorescent lights and in X-ray studies.

* Distal convoluted tubule: Once leaving the loop of Henle the thick ascending limb can optionally reabsorb and re increase the concentration in the nephrons .< ref > Reabsorbing and increasing the concentration is done by optionally absorbing Potassium ( K < sup >+</ sup >) and Hydrogen ( H < sup >+</ sup >) anions, while releasing water and the continued pumping out of Calcium ( Ca < sup >+</ sup >) and salt ( Na < sup >+</ sup > and Chlorine Cl < sup >-</ sup > ions ).

Calcium and bicarbonate ions within the water are then able to combine, to form calcium carbonate ( CaCO < sub > 3 </ sub >) as a precipitate.

Calcium ( Ca < sup > 2 +</ sup >) plays a pivotal role in the physiology and biochemistry of organisms and the cell.

Calcium phosphate is the name given to a family of minerals containing calcium ions ( Ca < sup > 2 +</ sup >) together with orthophosphates ( PO < sub > 4 </ sub >< sup > 3 -</ sup >), metaphosphates or pyrophosphates ( P < sub > 2 </ sub > O < sub > 7 </ sub >< sup > 4 -</ sup >) and occasionally hydrogen or hydroxide ions.

* Calcium Magnesium Acetate ( CaMg < sub > 2 </ sub >( CH < sub > 3 </ sub > COO )< sub > 6 </ sub >)

Calcium ( ) is the chemical element with symbol Ca and atomic number 20.

Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust.

Calcium is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.

Calcium has a higher electrical resistivity than copper or aluminium, yet weight-for-weight, due to its much lower density, it is a rather better conductor than either.

Calcium is the fifth-most-abundant element by mass in the human body, where it is a common cellular ionic messenger with many functions, and serves also as a structural element in bone.

Calcium, combined with phosphate to form hydroxylapatite, is the mineral portion of human and animal bones and teeth.

Calcium hydroxide ( slaked lime ) is used in many chemical refinery processes and is made by heating limestone at high temperature ( above 825 ° C ) and then carefully adding water to it.

Calcium is not naturally found in its elemental state.

Calcium is used