Coulombic forces of attraction

Debye-Hiickel theory The activity coefficient of an electrolyte depends markedly upon concentration. Jn dilute solutions, due to the Coulombic forces of attraction and repulsion, the ions tend to surround themselves with an atmosphere of oppositely charged ions. Debye and Hiickel showed that it was possible to explain the abnormal activity coefficients at least for very dilute solutions of electrolytes. 

Analogical molecular structure is possessed by other simple compounds such as potassium iodide, ammonium chloride, sodium hydroxide, barium nitrate, ammonium acetate and so on. In all these compounds there is a transfer of one or several electrons from one element to the other, positive and negative ions being thus formed, that are hold together in a crystal by electrostatic attraction. A bond of this kind is no genuine chemical bond in tbe correct meaning of the term, but is just,a result of Coulomb forces of attraction between opposite charges. 

The two steps of Eq. (2-13), ionization and dissociation, are influenced in different ways by solvents. The coulombic force of attraction between two oppositely charged ions is inversely proportional to the relative permittivity of the solvent, according to Eq. (2-17). Therefore, only solvents with sufficiently high relative permittivities will be capable... 

Coulomb force of attraction the hypothetical character of the last number may be once more emphasized. 

In the hydrogen atom, the electron moves in a circular orbit about the nucleus. Mechanically, the centripetal force that curves the path of the electron is balanced by the coulombic force of attraction between the oppositely charged particles (the negatively charged electron and the positively charged proton in the nucleus). 

Were we to simply add the ionization energy of sodium (496 kJ/mol) and the electron affin ity of chlorine (—349 kJ/mol) we would conclude that the overall process is endothermic with AH° = +147 kJ/mol The energy liberated by adding an electron to chlorine is msuf ficient to override the energy required to remove an electron from sodium This analysis however fails to consider the force of attraction between the oppositely charged ions Na" and Cl which exceeds 500 kJ/mol and is more than sufficient to make the overall process exothermic Attractive forces between oppositely charged particles are termed electrostatic, or coulombic, attractions and are what we mean by an ionic bond between two atoms... 

If two oppositely charged plates exist in a vacuum, there is a certain force of attraction between them, as stated by Coulomb s law ... 

The force of attraction, calculated from Coulomb s law, for a uniformly charged, spherical, particle in contact with a grounded, conducting substrate is simply... 

Since we have reason to believe that the order-disorder situation in ionic co-spheres, overlapping and merging as in Fig. 69, could give rise to forces of attraction or repulsion, superimposed on the Coulomb forces, we may inquire whether the observed facts as to activity coefficients may be correlated with the known behavior of the ions as regards viscosity and entropy. 

The force of attraction between two points of opposite electrical charge is given by Coulombs law ... 

The dimensionless dielectric constant, e, measures how we// a solvent can separate oppositely charged ions. The force of attraction (newtons) between ions of charge qt and q2 (coulombs) separated by distance r (meters) is... 

The force of attraction or repulsion between two charges is called the electrostatic or coulombic force. The term electrostatic implies that the charges are stationary or fixed in position. The magnitude of the electrostatic force between two fixed point charges is given by Coulomb s law ... 

It is true that all molecular and atomic forces ultimately find their root in the mutual behavior of the constituent parts of the atoms, viz., the nuclei and the electrons. They may theoretically all be derived from the fundamental wave equations. It is, however, convenient, as in other branches of physics and chemistry, to treat the various forms of mutual interaction of atoms as different forces, acting independently. We shall therefore follow the usual procedure and treat such forces as the nonpolar van der Waals (dispersion) forces, the forces of the electrostatic polarization of atoms or molecules by ions or by dipoles, the mutual attraction or repulsion Coulomb forces of ions and of dipoles, the exchange forces leading to covalent bonds, the repulsion forces due to interpenetration of electronic clouds, together with the Pauli principle, etc., all as different, independently acting forces. 

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