Salts of oxoacids

Because the ionic radius of [02] 0, it follows from the equation above that AC/(Sr02) is less negative than A 7(SrO). This result is in agreement with the data given in the question. 

Use data from the Appendices in the book where necessary. 

Show that this trend in values is consistent with the Kapustinskii equation. 

Ca02 is 270kJmol. Will the difference between the lattice energies of MgO and Mg02 be larger or smaller than 270kJmol Use the Kapustinskii equation to rationalize your answer. [Ans. Larger] 

Berylhum hydroxide is amphoteric and this sets it apart from the hydroxides of the other group 2 metals which are basic. In the presence of excess [OH] , Be(OH)2 behaves as a Lewis acid (eq. 12.25), forming the tetrahedral complex ion 12.7, but Be(OH)2 also reacts with acids, e.g. reaction 12.26. 

In this section, we give selected coverage of group 2 metal salts of oxoacids, paying attention only to compounds of special interest or importance. 

The carbonates of Mg and the later metals are sparingly soluble in water their thermal stabilities (equation 11.19) increase with cation size, and this trend can be rationalized in terms of lattice energies. The metal carbonates are much more soluble in a solution of CO2 than in water due to the formation of [HC03] . However, salts of the type M(HC03)2 have not been isolated. Hard water contains 

Permanent hardness is caused by other Mg and Ca salts (e.g. sulfates). The process of water softening involves passing the hard water through a cation-exchange resin (see Section 

Washing-machine detergents contain builders that remove Mg and Ca ions from washing water polyphosphates have been used for this purpose, but because phosphates are damaging to the environment (see Box 14.12), zeohtes (see Section 13.9) are used in preference. 

The water solubilities of M(OH)2 (M = Mg, Ca, Sr, Ba) increase down the group, as do their thermal stabilities with respect to decomposition into MO and H2O. Magnesium hydroxide acts as a weak base, whereas Ca(OH)2, Sr(OH)2 and Ba(OH)2 are strong bases. Soda lime is a mixture of NaOH and Ca(OH)2 and is manufactured from CaO and aqueous NaOH. Soda lime is easier to handle than NaOH and is commercially available, being used, for example, as an absorbent for CO2, and in qualitative tests for [NUi] salts, amides, imides and related compounds which evolve NH3 when heated with soda lime. 

Sulfates of Mg and Ca have important applications and those of CaS04 are described in Section 16.2. Hydrated calcium sulfate (CaS04-2H20, gypsum) occurs naturally 

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Mixtures of the sulfoxide with metal salts of oxoacids are powerful explosives. Examples are aluminium perchlorate, sodium perchlorate and iron(III) nitrate [1], The water in hydrated oxosalts (aluminium perchlorate, iron(III) perchlorate, iron(III) nitrate) may be partially or totally replaced by dimethyl (or other) sulfoxide to give solvated salts useful as explosives [2], Metal nitrates and perchlorates solvated with DMSO are generally powerfully explosive, and under certain conditions a violent reaction is easily triggered [3], Several other explosions involving perchlorates and the sulfoxide have been reported. 

Metal oxides containing single metalhc elements (binary oxides) and more than two metallic elements (double oxides and salts of oxoacids) are commonly used as catalysts in a variety of chemical reactions. Oxide and metallic catalysts are two major groups of industrial catalysts. In practice, most catalysts are produced from mixtures of more than two phases the phase primarily responsible for the catalysis is called the active component. 

The acid strength of metallic salts of oxoacids in the solid state (and hence the catalytic activity by acid catalysis) increases with electronegativity of the metal ion. ... 

The properties of alkali metal salts of most oxoacids depend on the oxoanion present and not on the cation thus we tend to discuss salts of oxoacids under the appropriate acid. However, we single out the carbonates and hydrogencarbonates because of their importance. Whereas Li2C03 is sparingly soluble in water, the remaining carbonates of the group 1 metals are very soluble. 

Aluminium to thallium salts of oxoacids and aqueous solution chemistry... 

Chapter 13 Aqueous solution chemistry and salts of oxoacids of germanium, tin and lead 381... 

SULFICYLBIS (METHANE) (67-68-5) CjHjOS (CH3)2S0 Combustible liquid [explosion limits in air (vol %) 2.6 to 63.0 flashpoint 203°F/95°C oc autoignition temp 419°F/215°C Fire Rating 2]. Violent or explosive reaction with strong oxidizers, acryl halides, aryl halides and related compounds, alkali metals p-bromobenzoyl acetanilide, boron compounds, especially hydrides iodine pentafluoride, magnesium perchlorate, methyl bromide, perchloric acid, periodic acid, silver fluoride, sodium hydride, potassium permanganate. Forms powerfully explosive mixtures with metal salts of oxoacids [iron(III)nitrate, phosphonic acid, sodium perchlorate]. On small fires, use dry chemicals or COj extinguishers. 

Bismuth commonly forms cations of + 3 charge. It forms the basic oxide Bi20j and salts of oxoacids such as Bi2(S04)3 and Bi(N03)3- Reaction of the metal with hahdes such as fluorine and chlorine results in a salt with the formula of BiXj. Because of the size of the metal atom, the linkages are more ionic than those found for other group members. 

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