By salts are meant hydrolyzing the reaction between water molecules and molecules of dissolved salts.As a result of this reaction are formed little- dissociated compound.The process can take place not only with salts, but in the case of the presence in the water of other solutes - carbohydrates, proteins, fats, or esters.Numerically, a reaction used two values - the degree of hydrolysis (β) and a constant salt hydrolysis (K [i]).
The reaction is usually observed change in the initial solution acidity.Instead of the organic solvent (water) can be used another type of solvent.However, in this case the reaction between the solvent and salt are called solvolysis.
is important to know that only those involved hydrolysis of the salts, which are derivatives of components of weak bases and acids.Salts derived from strong acids and bases, the hydrolysis reaction is not exposed.
to characterize the completeness of the process, a special definition - the degree of hydrolysis (β).The degree of hydrolysis determines the ratio of the value of the concentration of molecules that undergo hydrolysis (C [hydraulic]) to the original (initial) concentration of salt has dissolved (C [ref.]).Mathematically, this can be expressed by the following equation: β = C [hydraulic] / C [ref.].
degree of reaction depends on three factors:
- the nature of the ions that make up the salt;
- ion concentration of salt;
- solution temperature.
degree of hydrolysis tends to increase with decreasing the dissociation constant of the weak acid or base, as well as reducing the degree of salt concentration and increasing temperature.
reaction may occur at appreciable extent only in dilute solutions.Therefore, if the value of C [H20] is roughly constant, then it is possible to calculate the derivative and the value of K [i] (constant or hydrolysis).Depending on the relative properties of the acids and bases from which salts are formed, hydrolysis may occur in one of three schemes, and therefore a constant salt hydrolysis calculated differently.
Hydrolysis of salts, which are derived from parts of a strong acid and weak base (another name for the process - hydrolysis of the cation)
constant hydrolysis is determined by the following formula: [i] = K [W] / K [the base]where R [W] - the result of the ion product of water (C [H] + C [OH (-)]).
From the expression hydrolysis constants can be seen that with decreasing force an increase in the base hydrolysis constant value and, consequently, the degree of hydrolysis.In turn, the degree of hydrolysis tends to increase with decreasing values of forces the base and the degree of concentration of salts in the solution.Increasing reaction temperature also increases hydrolysis constants and higher values of the degree of hydrolysis.
Hydrolysis of salts, which are derived from a strong base and a weak acid (another name for the process - hydrolysis of the anion)
hydrolysis constants calculated with the following formula: [i] = K [W] / K [acid], where the value of K[acid] - is the dissociation constant for the weak acid.
Hydrolysis of salts, which are derived from a weak base and a weak acid (another name - the hydrolysis of cations and anions)
In this case, the constant hydrolysis will determine the dissociation constant of a weak base and a weak acid.It is calculated by the following formula: [i] = K [W] / K [acid] * K [the base].
value hydrolysis process
reactions occurring in the hydrolysis process is widely used in modern industrial processes.For example, such a reaction is used to purify water from harmful impurities and the coarse colloidal series.For this purpose special precipitation of hydroxides of iron and aluminum, obtained through hydrolysis of iron sulfates, iron chlorides and sulphates of aluminum.
Hydrolysis - is an important part of the process of digestion of living organisms on Earth.Most of the energy needed for the existence of the organism, is stored as adenosine triphosphate (ATP).Isolation of the energy takes place through a process involving the hydrolysis of ATP.
