Alkaline earth metals, magnesium, cadmium

Although the word alabaster is sometimes applied to a kind of translucent gypsum (calcium sulfate), Egyptian alabaster was a form of calcite 

Dioscorides Pedanios said that calx viva (quicklime) was made by heating shells of sea fishes called Buccinoe (whelks), pebble stones, or marble (75). 

In about 975 A.D. the Persian pharmacist Abu Mansur Muwaffaq wrote his Book of Pharmacological Principles, in which he described for the first time the use of the plaster of Paris bandage for bone fractures (76). 

Sir Humphry Davy, 1778—1829. Professor of chemistry and lecturer at the Royal Institution, London. Scientist, poet, and humanitarian. Donor of the Davy Medal. 

From Muspratt s Chemistry, Theoretical, Practical and Analytical  

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Group IIB and know that this means the group of elements zine. cadmium and mercury, whilst Group IIA refers to the alkaline earth metals beryllium, magnesium, calcium, barium and strontium. 

Reduction to Gaseous Metal. Volatile metals can be reduced and easily and completely separated from the residue before being condensed to a hquid or a soHd product in a container physically separated from the reduction reactor. Reduction to gaseous metal is possible for 2inc, mercury, cadmium, and the alkah and aLkaline-earth metals, but industrial practice is significant only for 2inc, mercury, magnesium, and calcium. 

Although zinc is formally a 4-block element, some of its chemical properties are similar to those of the alkaline earth metals, especially those of magnesium. This is mainly due to zinc s exclusive exhibition of the +2 oxidation state in all its compounds and its appreciable electropositive character. With a standard potential of —0.763 V, zinc is considerably more electropositive than copper and cadmium. 

Intimate mixtures of chlorates, bromates or iodates of barium, cadmium, calcium, magnesium, potassium, sodium or zinc, with finely divided aluminium, arsenic, copper carbon, phosphorus, sulfur hydrides of alkali- and alkaline earth-metals sulfides of antimony, arsenic, copper or tin metal cyanides, thiocyanates or impure manganese dioxide may react violently or explosively, either spontaneously (especially in presence of moisture) or on initiation by heat, friction, impact, sparks or addition of sulfuric acid [1], Mixtures of sodium or potassium chlorate with sulfur or phosphorus are rated as being exceptionally dangerous on frictional initiation. 

In many of its features, the chemistry of manganese(II) spans that of the alkaline earth metals (especially magnesium(II) and that of the later first row transition metals. There are also parallels with cadmium(II) rather than zinc(II). These are all related to the more significantly ionic bonding for manganese and to the size of the metal ion . 

Other alkaline earth metal oxides and related Group II metal oxides were screened for activity. Tests indicated that magnesia-zinc oxide combinations were about as efficient as magnesia alone. Calcium oxide, zinc oxide, and cadmium oxide were all catalysts for the reaction but were not as effective as magnesium oxide. Efficiencies of these oxides were increased by supporting them on activated alumina. In addition, it was found that sodium and lithium compounds deposited on activated alumina were active cat-... 

The NMR spectra of normal alkoxides of heavier alkaline earth metals (Ca, Sr, Ba), beryllium as well as magnesium, zinc, cadmium and mercury do not appear to have been studied, probably owing to their highly polymeric nature and insolubility in common organic solvents. 

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