Autodissociation, or autoionization is the spontaneous separation of molecules into ions. A molecule, or a set of molecules will split up to form a number of positive charged particles (cations) and negative charged particles (anions). Autodissociation is usually associated with protic solvents; compounds that can supply protons (H+ ions) to stronger bases.
Water (H2O) undergoes autodissociation. The chemical formula representing this reaction is: 2 H2O = H3O+ + OH-
or simplified (but a less-correct representation of chemical structures): H2O = H+ + OH-
This is an equilibrium reaction, which means that under ordinary conditions water consists of both H2O molecules, and the H3O+ and OH- ions.
The extent of autodissociation of water is very small. This is expressed by the equilibrium constant: K'25 °C = [H+][OH-]/[H2O] = (1.0·10-14)/55.56
The equilibrium constant indicates that at 25 °C, for every 55.6 moles of water, only 1.0·10-14 moles are dissociated in the corresponding ions (approximately 1 pair of ions per 5.6·1015 molecules of water).
Since the 55.56 mol/L concentration of water molecules is essentially constant, it is usually omitted. Thus: K25 °C = [H+][OH- ] = 1.0·10-14 mol2/L2 is used. However, the autodissociation constant is only constant for a given temperature, and generally increases for increasing temperature.
Autodissociation is not restricted to water alone: many other compounds undergo the same type of reaction: 2 HCl = H2Cl+ + Cl- (hydrochloric acid) 2 HF = H2F+ + F- (hydrofluoric acid) 2 H2SO4 = H3SO4+ + HSO4- (sulfuric acid) 2 NH3 = NH4+ + NH2- (Ammonia)
Keep in mind that these simple equations describe only part of the chemical dissociation reactions that occur in reality. For instance, the primary ions observed in water can undergo further solvation reaction to ions such as H5O2+, H7O3+, and H9O4+.
Dissociation is a dangerous mental disease.
Dissociation is a process that occurs along a spectrum of severity
Dissociation is the decomposition of a substance in ions in a solution.Generally is a decomposition.
Dissociation of sodium chloride in water solution: NaCl -----------Na+ + Cl-
The meaning is the percent of the original molecule dissociated during the process of dissociation.
The dissociation factor is 1, because the molecule can't break apart.
The dissociation constant of pure water is 1.9E-5.
The Correct Answer is: Ionization and Dissociation.
The meaning of the term dissociation in chemistry is splitting of a compound (in water solution) in ions, radicals etc. Thermal dissociation is the reversible process performed by heating and when the molecule is splitted generally in a single step.
The strength of an acid or the measure of its tendency to release proton ions (H+) can be indicated from its dissociation constant which is called Ka. The acid dissociation constant, pKa , is the negative logarithm of dissociation constant (Ka).
salt
dissociation