Calcium

Calcium has been used by human kind for years unknowingly, before the actual discovery of calcium singularly. Used within the limestone (calcium chloride) statues, marble monuments, and mortar (cement-like material), calcium is and has always been a huge part of human life. Humphry Davy, an english chemist, known for his contributions to the scientific world of electrochemistry, discovered calcium along side potassium, sodium, magnesium, strontium, and barium. In 1808, after inventing a method of electrolysis, Davy was able to isolate all of these elements, but most importantly calcium!

Calcium is possibly one of the most well known elements and also remains essential to human and animal life. Designated in group two of the periodic table, this Alkaline Earth Metal, is found abundantly within the Earth's crust. It is even the fifth most abundant element on earth, estimated at 3.64%.

In a neutral state, calcium has 20 protons 20 electrons and 20 neutrons. This adds up to an 40 gram atomic weight per mole. Calcium can readily become an ion of +2. This means calcium will lose two electrons to form a positive ion. Calcium is also a fairly soft metal with a luster, but becomes dull when it reacts with oxygen because a coating of grey calcium oxide will form.

In nature, calcium will be found in an ore combined with another substance to form a mineral because it is quite reactive. It readily reacts with oxygen to form calcium oxide and also reacts with the halogens; fluorine, chlorine, bromine, iodine, and astatine. Chlorine can also react with cold water, acids, and nonmetals. Because chlorine is so reactive, it will always be found as some form of a compound. It occurs in aragonite, calcite, chalk, limestone, marble, and travertine, and in oyster shells and coral.

To extract calcium a process called electrometallurgy can be used. In this process, an electrical current flows through molten calcium chloride and pure calcium is the product; however, there is not a big demand for pure calcium.

Calcium is fairly light with a density of 1.54 grams per cubic centimeter, which makes it more resistant to electricity. The relative melting point of calcium is 850°C and the boiling point is 1,440°C. As you can see these numbers are extremely high and make calcium a hard substance to find in a gaseous or liquid state.

Attaining the combustion of calcium is even more difficult than magnesium; however, once attained, calcium will give off an orange-red hue.

Calcium can be an be found as calcium-40, calcium-42, calcium-43, calcium-44, calcium-46, and calcium-48. Both calcium-45 and calcium-47 are radioactive isotopes, meaning they have been made radioactive to help with research and medecine. Calcium-45 has been used to examine the process calcium will naturally take in soil or fertilizer. It has also been used in glassy materials, detergents, and water purification systems to trace impurities that cannot be seen with the human eye so they send out a radioactive signal to indicate to the detectors in systems there is a problem. Calcium-47 along with calcium-45 can be used to study how calcium is used in the human body. When doctors believe a body is not regulating nerve messages or building bone incorrectly they will inject this isotope of calcium to be followed and traced. Calcium isotopes help doctors and many other people make new discoveries about the human body and nature as well.

Calcium cannot be purchased by the public alone because it is too reactive to even be transferred by any means without at the least oxidation occurring. The average calcium supplement can range anywhere from 10 dollars to 50 dollars depending on the level of calcium and the form of the supplement.

A main location to designate the production or mining of calcium is very hard to find considering calcium is so abundant and is commonly found in cow's milk, ocean, rock, and other natural sources easy to come by. I could not find a specific country or general area where calcium is known to come from.

___________________
Uses for Calcium:
-as a metal
1. Getter- used to retrieve unwanted chemicals from a system by sending out signals or actually removing the unwanted substance. Used in items such as copper, steel, and electric light bulbs
2. Used as an alloy. For example cerium, which is what is used in flints (create the spark) of a lighter

-as a compound
1. Limestone-used for building, statues,art, naturally found
2. Cement and mortars for building in construction
3. Production of cheese, influence the reactivity of rennin in bringing about the coaggulation of milk
4. Calcium hydroxide solution (Ca(OH)2) (also known as limewater) is used to detect the presence of carbon dioxide by being bubbled through a solution. It turns cloudy where CO2 is present.
5. Calcium arsenate (Ca3(AsO4)2) is used in insecticides.
6. Calcium carbide (CaC2) is used to make acetylene gas (for use in acetylene torches for welding) and in the manufacturing of plastics.
7. Calcium chloride (CaCl2) 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.
8. Calcium cyclamate (Ca(C6H11NHSO3)2) was used as a sweetening agent but is no longer permitted for use because of suspected cancer-causing properties.
9. Calcium gluconate (Ca(C6H11O7)2) is used as a food additive and in vitamin pills.
10. Calcium hypochlorite (Ca(OCl)2) is used as a swimming pool disinfectant, as a bleaching agent, as an ingredient in deodorant, and in algaecide and fungicide.
11. Calcium permanganate (Ca(MnO4)2) is used in liquid rocket propellant, textile production, as a water sterilizing agent and in dental procedures.
12. Calcium phosphate (Ca3(PO4)2) 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.
13. Calcium phosphide (Ca3P2) is used in fireworks, rodenticide, torpedoes and flares.
14. Calcium stearate (Ca(C18H35O2)2) 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.
15. Calcium sulfate (CaSO4·2H2O) is used as common blackboard chalk, as well as, in its hemihydrate form better known as Plaster of Paris.
16. Calcium tungstate (CaWO4) is used in luminous paints, fluorescent lights and in X-ray studies.
17. Hydroxylapatite (Ca5(PO4)3(OH), but is usually written Ca10(PO4)6(OH)2) makes up seventy percent of bone. Also carbonated-calcium deficient hydroxylapatite is the main mineral of which dental enamel and dentin are comprised.

More you should know...
We all have heard of calcium before and most of us link calcium to strong bones, strong teeth, and dairy products. The truth of the matter is our bodies need calcium to survive. Hydroxyapatite is the substance found in milk which provides calcium to make our bones and teeth strong, hard, and resilient. Furthermore, calcium does not only supply for our bones and teeth. The right amount of calcium keeps your heart rate normal and your muscles as well as nerves functioning correctly at all times. Adequate amounts of calcium can be attained by consuming the following foods; milk and other dairy products; green, leafy vegetables; seafood; nuts; and dried beans, orange juice, breakfast cereals, breads, and other fortified food products. Some forms of calcium deficiency can lead to osteoporosis, weakening of the bones, and depleted calcium stores in bones while another, called Hypocalcemia, can cause renal failure without treatment and must be carefully watched. Calcium has recently even been found to contain anti-carcinogenic vitamin D supplements, meaning calcium may contain cancer preventing characteristics and is now being researched vigorously. You probably don't think of calcium as precious metal because it is not hard to come by and is rather commonly used; however, the variety of uses and calcium's importance to human life may make us realize that calcium is in fact extremely precious.

Works Cited:
http://www.chemistryexplained.com/elements/A-C/Calcium.html
http://en.wikipedia.org/wiki/Calcium#History
http://ods.od.nih.gov/factsheets/calcium/