Electroneutrality rule

With a weak acid such as hydrochloric and p-toluenesulphonic acids, [H+X ] and [H+] are negligibly small compared with [HX], so that eqn. 4.66 becomes Chx = [HX] also as in acid solution [S ] from autoprotolysis of the solvent H2S can be neglected, the electroneutrality rule reduces to... 

Once the above system of I in solvent HS has been studied, one can determine the properties of an additional base B (e.g. pyridine) in this medium. Here the electroneutrality rule yields... 

The first rule is the Principle of electroneutrality (Rule 11.1) which restricts the chemical composition of inorganic compounds to those in which the net charge is zero. In the context of the bond valence model this rule can be stated as ... 

Once the basic structure has been determined, bond valences can be used to resolve a number of problems of interpretation. Diffraction experiments can identify the location of each atom, but cannot identify its oxidation state. In most structures the oxidation state is determined by the requirements of electroneutrality (Rule 11.1), but in some structures more than one assignment is possible. Bond valence sums can usually resolve this ambiguity. 

A variety of defect formation mechanisms (lattice disorder) are known. Classical cases include the - Schottky and -> Frenkel mechanisms. For the Schottky defects, an anion vacancy and a cation vacancy are formed in an ionic crystal due to replacing two atoms at the surface. The Frenkel defect involves one atom displaced from its lattice site into an interstitial position, which is normally empty. The Schottky and Frenkel defects are both stoichiometric, i.e., can be formed without a change in the crystal composition. The structural disorder, characteristic of -> superionics (fast -> ion conductors), relates to crystals where the stoichiometric number of mobile ions is significantly lower than the number of positions available for these ions. Examples of structurally disordered solids are -> f-alumina, -> NASICON, and d-phase of - bismuth oxide. The antistructural disorder, typical for - intermetallic and essentially covalent phases, appears due to mixing of atoms between their regular sites. In many cases important for practice, the defects are formed to compensate charge of dopant ions due to the crystal electroneutrality rule (doping-induced disorder) (see also -> electroneutrality condition). 

The Electroneutrality Rule and other chemical considerations usually lead to an unambiguous assignment of the atomic valences. If the number of bonds is less than the number of atoms, atomic valences, combined with the Valence Sum Rule expressed mathematically by Equation 10.5, are sufficient to assign the bond valences uniquely... 

The electroneutrality rule is therefore satisfied in both the cathode and anode compartments. 

The interiors of such phases are electrically neutral because the electroneutrality rule is valid for any arbitrary part of the phase [compare Eq. (21.1)] ... 

A straightforward modeling follows the electroneutrality rule. Attention must be paid when substitution or charged defects is under scrutiny. 

The values of i calculated fromEq. 2.105 on v(M) in different molecules, give the average (for 700 molecular halides and chalcogenides) of e = 0.5e, in agreement with Pauling s famous Electroneutrality Rule [480,481] which states that net charges of atoms in stable molecules and crystals should not exceed Yi, even though later he softened this limitation to 1 [475]. This principle later has been proved theoretically, confirmed experimentally and now plays a key role in the description of electronic structure of molecules and crystals. 

The sum of the oxidation numbers of aU atoms that constitute a molecule is equal to zero (electroneutrality rule). 

The first is the electroneutrality rule (12). Because the atoms of the core-and-valence-shell model are all electrically neutral and all the charges have been conserved during the derivation of the ionic model, the array of charged ions in the ionic model must also be electrically neutral. 

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