Magnesium (12)

Magnesium is a grayish-white, fairly tough metal. Magnesium is the eighth most abundant element in the earth's crust although not found in its elemental form. It is a Group 2 element (Group IIA in older labelling schemes). Group 2 elements are called alkaline earth metals. Magnesium metal burns with a very bright light.

Magnesium is an important element f...or plant and animal life. Chlorophylls are porphyrins [a group of complex elements primarily found in tissues – heme in the blood being another example- most naturally occurring] based upon magnesium. All chemical reactions in the body require an enzyme system to help the biochemical reaction take place. Magnesium is a critical co-factor in more than 300 enzymatic reactions in the human body, particularly nucleic acid enzymatic directed reactions. [An enzyme system generally consists of three parts. They are a specific protein molecule, another smaller organic compound, which is often a vitamin, such as pyridoxine or vitamin B6, and finally a charged mineral, such as zinc, copper, manganese or magnesium.] The adult human daily requirement of magnesium is about 0.3 g per day.

•Name: Magnesium
•Symbol: Mg
•Atomic number: 12
•Atomic weight: 24.3050
•Standard state: solid at 298 K
•CAS Registry ID: 7439-95-4
•Group in periodic table: 2
•Group name: Alkaline earth metal
•Period in periodic table: 3
•Block in periodic table: s-block
•Color: silvery white
•Classification: Metallic

Historical information

Magnesium was discovered by Sir Humphrey Davy at 1755 in England. Origin of name: from the Greek word "Magnesia", a district of Thessaly. In 1618 a farmer at Epsom in England attempted to give his cows water from a well. This they refused to drink because of the water's bitter taste. However the farmer noticed that the water seemed to heal scratches and rashes. The fame of Epsom salts spread. Eventually they were recognized to be magnesium sulphate, MgSO4. Black recognized magnesium as an element in 1755. It was isolated by Davy in 1808 who electrolyzed a mixture of magnesia (magnesium oxide, MgO) and mercuric oxide (HgO). Davy's first suggestion for a name was magnium but the name magnesium is now used.

Sometime prior to the autumn of 1803, the Englishman John Dalton was able to explain the results of some of his studies by assuming that matter is composed of atoms and that all samples of any given compound consist of the same combination of these atoms. Dalton also noted that in series of compounds, the ratios of the masses of the second element that combine with a given weight of the first element can be reduced to small whole numbers (the law of multiple proportions). This was further evidence for atoms. Dalton's theory of atoms was published by Thomas Thomson in the 3rd edition of his System of Chemistry in 1807 and in a paper about strontium oxalates published in the Philosophical Transactions. Dalton published these ideas himself in the following year in the New System of Chemical Philosophy