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  2. Bond valence method - Wikipedia

    en.wikipedia.org/wiki/Bond_valence_method

    R i is the observed bond length, R 0 is a tabulated [1] parameter expressing the (ideal) bond length when the element i has exactly valence 1, and b is an empirical constant, typically 0.37 Å. Another formula for v i {\displaystyle v_{\text{i}}} has also been used: [ 2 ]

  3. Enthalpy change of solution - Wikipedia

    en.wikipedia.org/wiki/Enthalpy_change_of_solution

    The energy released by the solvation of the ammonium ions and nitrate ions is less than the energy absorbed in breaking up the ammonium nitrate ionic lattice and the attractions between water molecules. Dissolving potassium hydroxide is exothermic, as more energy is released during solvation than is used in breaking up the solute and solvent.

  4. Tripotassium phosphate - Wikipedia

    en.wikipedia.org/wiki/Tripotassium_phosphate

    Tripotassium phosphate, also called tribasic potassium phosphate [3] is a water-soluble salt with the chemical formula K 3 PO 4. (H 2 O) x (x = 0, 3, 7, 9). [ 4 ] Tripotassium phosphate is basic: a 1% aqueous solution has a pH of 11.8.

  5. Ionic strength - Wikipedia

    en.wikipedia.org/wiki/Ionic_strength

    The ionic strength of a solution is a measure of the concentration of ions in that solution. Ionic compounds, when dissolved in water, dissociate into ions. The total electrolyte concentration in solution will affect important properties such as the dissociation constant or the solubility of different salts. One of the main characteristics of a ...

  6. Standard enthalpy of formation - Wikipedia

    en.wikipedia.org/wiki/Standard_enthalpy_of_formation

    For a gas, it is the hypothetical state the gas would assume if it obeyed the ideal gas equation at a pressure of 1 bar. For a gaseous or solid solute present in a diluted ideal solution , the standard state is the hypothetical state of concentration of the solute of exactly one mole per liter (1 M ) at a pressure of 1 bar extrapolated from ...

  7. Formula unit - Wikipedia

    en.wikipedia.org/wiki/Formula_unit

    In most cases the formula representing a formula unit will also be an empirical formula, such as calcium carbonate (CaCO 3) or sodium chloride (NaCl), but it is not always the case. For example, the ionic compounds potassium persulfate ( K 2 S 2 O 8 ), mercury(I) nitrate Hg 2 (NO 3 ) 2 , and sodium peroxide Na 2 O 2 , have empirical formulas of ...

  8. Debye–Hückel theory - Wikipedia

    en.wikipedia.org/wiki/Debye–Hückel_theory

    The extended Debye–Hückel equation provides accurate results for μ ≤ 0.1. For solutions of greater ionic strengths, the Pitzer equations should be used. In these solutions the activity coefficient may actually increase with ionic strength. The Debye–Hückel plot with different values for ion charge Z and ion diameter a

  9. Hückel method - Wikipedia

    en.wikipedia.org/wiki/Hückel_method

    This is more than the naive π-bond order of (for a total bond order of ) that one might guess when simply considering the Kekulé structures and the usual definition of bond order in valence bond theory. The Hückel definition of bond order attempts to quantify any additional stabilization that the system enjoys resulting from delocalization.