Water reaction with alkali metals

B.17 (a) Cd, metal (b) Cr, metal (c) Sb, metalloid B.19 Li, 3 Na, 11 K, 19 Rb, 37 Cs, 55 Fr, 87. All the alkali metals react with water to produce hydrogen. Lithium reacts gently the reaction becomes more vigorous down the group. The melting points decrease down the group. [Pg.1053]

Reaction with Water The most well-known and dramatic reaction of the alkali metals is with water to yield hydrogen gas and an alkali metal hydroxide, MOH. In fact, it s this reaction that gives the elements their group name The solution of metal hydroxide that results from adding an alkali metal to water is alkaline, or basic. [Pg.218]

The use of water, which has strong OH-bonds, should eliminate hydrogen abstraction from the matrix. However, the yield of cyclohexane was still higher than that of cyclohexene. This result can be attributed to the formation of hydrogen atoms by reaction of some alkali metal atoms with water instead of with cyclohexyl bromide. These hydrogen atoms could then either combine with cyclohexyl radicals to give cyclohexane or add to cyclohexene (formed from a previous disproportionation reaction) to regenerate cyclohexyl radicals. [Pg.68]

All alkali metals react with water to produce hydrogen gas and the corresponding alkali metal hydroxide. A typical reaction is that between lithium and water ... [Pg.90]

Because all alkali metals react with water, it is not possible to measure the standard reduction potentials of these metals directly as in the case of, say, zinc. An indirect method is to consider the following hypothetical reaction... [Pg.880]

The rate of the alkaU metal reaction with water, and therefore its vigor, is enhanced by the successively lower melting points of the alkali metals as we move down the column. The low melting points of the heavier metals allow the emitted heat to actually melt the metal, increasing the reaction rate. [Pg.368]

Potassium superoxide, KO2, can also be used for this purpose. The oxides, peroxides, and superoxides of the alkali metals react with water to form basic solutions. The reaction of an alkali metal oxide with water is an acid-base reaction that produces the alkali metal hydroxide. [Pg.988]

All the alkali metals react with water to give MOH and H2. Thus, Y must be H2. In the first reaction, X could be M2O, M2O2, or MO2. However, the second reaction has only one product. Because M2O2 and MO2 react with water to give MOH and other products, we know that X cannot be M2O2 or MO2. Thus, X must be M2O. The only alkali metal that reacts with oxygen to give M2O as the principal product is lithium, so M must be Li. The complete chemical equations are... [Pg.1001]

The stability of the alkali metal ozonides increases from Li to Cs alkaline-earth ozonides exhibit a similar stability pattern. Reaction of metal ozonides with water proceeds through the intermediate formation of hydroxyl radicals. [Pg.492]

Again, we see that the alkali metals display likeness in their reactions with water. Furthermore, the reaction products always include an aqueous ion of the alkali element in which one electron has been removed, giving a 1+ ion. [Pg.96]

B.20 List the names, symbols, and atomic numbers of the alkali metals. Characterize their reactions with water and describe their trend in melting points. [Pg.46]

Practically all metals can be passivated. Even lithium, which is a highly active alkali metal, can be passivated in concentrated LiOH solution this is the reason for its greatly reduced rate of reaction with water. [Pg.306]

The formation of an anodic film on alkali metal anodes is mentioned in (129b). If it can be confirmed that Li is not unique in its reaction with water, as it is claimed in (123-124), then Na may also develop such a film in contact with H2O or non-aqueous liquids and so be protected. Design variations in Na-H20 primary batteries are described (130-132). [Pg.285]

Lithium Carbonate. Add a saturated sodium carbonate solution to 2-3 ml of a saturated lithium sulphate or chloride solution. What do you observe Write the equation of the reaction. Acquaint yourself with the solubility of the alkali metal carbonates in water. [Pg.183]

Put several pieces of chromium into test tubes and test its reaction with water, alkalies, and also with dilute and with concentrated solutions of hydrochloric, sulphuric, and nitric acids (in the cold and with heating). Write the equations of the reactions. What position does chromium occupy in the electrochemical series of metals ... [Pg.222]

Like all reactions of the alkali metals, the reaction with water is a redox process in which the metal M loses an electron and is oxidized to M +. At the same time, a hydrogen from water gains an electron and is reduced to H2 gas, as can be seen by assigning oxidation numbers to the various substances in the usual way. Note that not all hydrogens are reduced those in the OH - product remain in the +1 oxidation state. [Pg.219]

Reaction with Ammonia The alkali metals react with ammonia to yield H2 gas plus a metal amide, MNH2. The reaction is exactly analogous to that between an alkali metal and water. [Pg.219]

A fairly general procedure, which has also been used on the industrial scale, involves heating the alkali metal sulphonate with either sodium or potassium hydroxide in the presence of a small amount of water to aid the fusion process. The reaction mechanism may be formulated as a bimolecular nucleophilic addition-elimination sequence. [Pg.970]

Record alkali metal densities and reactions with water and acids. [Pg.242]

Already familiar is the convenient laboratory preparation of elementary hydrogen by reduction of acids. Generally those metals lying between magnesium and tin in oxidation potential are appropriate. Less convenient but more spectacular is the production of hydrogen from action of the alkali metals on water. For small quantities of hydrogen, reaction of metal hydrides with water has been used such hydrides will be considered later in the chapter. Commercial preparations of H2 by reduction of steam with iron or coke and, finally, by the electrolysis of water should be recalled. [Pg.23]

Pentafluoropropan-l-ol (1) can also be prepared by interacting tetrafluoroethene with an alkali metal fluoride or an alkaline earth metal fluoride, followed by reaction with formaldehyde, and Anally by hydrolysis of the metal alcoholate with water. ... [Pg.363]

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