The most important in metabolic processes is the hydrolysis of salts. What it is? Together we will look for the answer to this question. Let us dwell in more detail on the features of this chemical interaction in organic and inorganic chemistry.
Definition
Water is one of the most active substances. It is able to influence different classes of compounds of organic and inorganic nature: esters, proteins, carbohydrates, salts, fats. Arguing over what hydrolysis is, it should be noted that this process occurs in the aquatic environment. As a result, the acidity of the solution changes in comparison with the initial indicator.
What is hydrolysis? In the chemistry of inorganic compounds, this process is most often associated with salts, i.e., the interaction of cations and salt anions with molecules of a polar solvent (water) is analyzed. The process is accompanied by a shift in the equilibrium of electrolytic dissociation of water.
What is hydrolysis? This is a reversible interaction between water and salt ions, which leads to a change in the equilibrium in the solution between hydroxyl and hydrogen ions.
Flow pattern
This process is the result of polarizing mutual action in an aqueous solution of salt ions with their hydration shell. The greater the interaction, the brighter the hydrolysis.
Cations in solution are bound by donor – acceptor bonds with water molecules. Oxygen atoms, which have two lone electron pairs, act as a donor. The cation, which owns free atomic orbitals, becomes an acceptor. The polarizing effect of it on water depends on the charge of the cation.
Anions due to hydrogen bonds interact with water. With their strong influence, the proton can completely detach, therefore, among the products there will be anions of the form HS , 3‾.
Process reversibility
Arguing over what hydrolysis is, it should be noted that this is a reversible neutralization reaction, accompanied by the release of energy (exothermic). There are several options for this process, the result of which directly depends on the composition of the starting salt. Each of them is considered as part of a school chemistry course.
Salt hydrolysis options
There are several variations in which the reaction for a salt in an aqueous solution can be considered. If it is formed by a strong acid and a weak base, then there will be an acid and a basic salt among the products. A typical example is copper (II) chloride.
What is hydrolysis of a salt that is formed by a weak base and a weak acid? This is an irreversible process, which is accompanied by the formation of a precipitate (insoluble base) and volatile acid. Thus, we are talking about complete (in cation and anion) hydrolysis.
A typical case of hydrolysis of a salt of this species is ammonium acetate (CH 3 COONH 4). The reaction proceeding in such a case can be represented as follows:
NH4 + + CH 3 COO - + HOH = NH 4 OH + CH 3 COOH
Among the products it is necessary to note weak acetic acid and weak ammonium hydroxide.
What is the degree of hydrolysis? Depending on the strength of the acid and base, the dissociation constant takes different values:
if K D of the base is greater than that of acid, the medium is alkaline;
if K D of the base is less than that of acid, the medium is acidic.
For the hydrolysis of ammonium acetate K D (NH 4 OH) = 1.8 · 10 - 5; K D (CH 3 COOH) = 1.8 · 10 - 5, so the reaction will be neutral.
Complete hydrolysis is considered the reason that some salts cannot be prepared in aqueous solution. For example, aluminum sulfide is formed only from simple substances when heated. If moisture gets on it, it decomposes with the formation of aluminum hydroxide and hydrogen sulfide.
For salts that are formed by strong acid and alkali (soluble base), hydrolysis does not occur. The environment in their aqueous solutions is neutral; indicators do not change their initial color in them.
Amino Acid Formation
Let’s try to find out what hydrolysis of proteins is. These natural polymers are a sequence of amino acid residues that are joined together by a peptide (amide) bond. When boiling with alkalis or with acids, as well as under the influence of enzymes, protein molecules decompose into other chemical compounds, and in the end they transform into a mixture of a-amino acids.
Hydrolysis of proteins is important from a biological point of view. When molecules enter the intestines and stomach of a person or animal, they break down into amino acids. They are again synthesized into protein compounds that are specific to a particular living organism. Among the products of protein hydrolysis, purine bases, phosphoric acid, and carbohydrates were found.
Under their influence, for example, during heating, with shaking, the action of radiation, the spatial structure that is characteristic of a protein molecule is destroyed. Denaturation is irreversible or reversible, but the primary structure (sequence of amino acids) remains unchanged.
Fat Features
These organic compounds have certain characteristics. What is fat hydrolysis? By this is meant the hydrolytic decomposition of glycerides.
The following options are distinguished:
saponification in an enzymatic or sulfuric acid environment;
hydrolysis in an alkaline environment;
hydrogenation (conversion from liquid to solid fat).
To summarize
Hydrolysis is a process that is inextricably linked to the aquatic environment. Depending on which particular substance is the source, various reaction products may also form.