Alkaline earth metals reaction with hydrogen

Lithium and Alkaline-Earth Metals. With these elements X/Xo is usually less than one, and the inhibiting eflFect increases with Xo. For these particular values of X , we will assume that the inhibiting eflFect is the only one that exists, i.e., V2 = 2- Furthermore, as was suggested by Cotton et al. (2), we will assume that the additive metal reacts with some species of the flame to produce hydroxyl radicals which rapidly remove soot. It is well known that lithium easily forms the hydroxide LiOH via the reaction Li + H2O LiOH + H. Likewise, alkaline-earth metals can produce hydrogen atoms via equivalent reactions M -f H2O 1 2... 

Table 23-4 summarizes some reactions of the alkaline earth metals, which, except for stoichiometry, are similar to the corresponding reactions of the alkali metals. Reactions with hydrogen and oxygen were discussed in Sections 6-7 and 6-8. 

Explosive reactions can occur between oxygen and a wide range of chemicals including organic compounds (such as acetone, acetylene, secondary alcohols, hydrocarbons), alkali and alkaline earth metals, ammonia, biological specimens previously anaesthetized with ether, hydrogen and foam rubber. 

Hydrogen can be prepared by the reaction of water or dilute acids on electropositive metals such as the alkali metals, alkaline earth metals, the metals of Groups 3, 4 and the lanthanoids. The reaction can be explosively violent. Convenient laboratory methods employ sodium amalgam or calcium with water, or zinc with hydrochloric acid. The reaction of aluminium or ferrosilicon with aqueous sodium hydroxide has also been used. For small-scale preparations the hydrolysis of metal hydrides is convenient, and this generates twice the amount of hydrogen as contained in the hydride, e.g. ... 

Section 20.1 deals with the processes by which these metals are obtained from their principal ores. Section 20.2 describes the reactions of the alkali and alkaline earth metals, particularly those with hydrogen, oxygen, and water. Section 20.3 considers the redox chemistry of the transition metals, their cations (e.g., Fe2+, Fe3+), and their oxoanions (e.g., Cr042-). ... 

The compounds formed by the reaction of hydrogen with the alkali and alkaline earth metals contain H- ions for example, sodium hydride consists of Na+ and H- ions. These white crystalline solids are often referred to as saline hydrides because of their physical resemblance to NaCL Chemically, they behave quite differently from sodium chloride for example, they react with water to produce hydrogen gas. Typical reactions are... 

Alkaline earth metal A metal in Group 2 of file periodic table, 31 hydrogen reactions with, 542 oxygen reactions with, 543-544 reactions, 54U, 552q water reactions with, 542... 

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