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It is called chemical reaction to the process by which one or more chemical substances called in this context "reactants" are transformed and give rise to others, designated in this context as "products". In addition to a reorganization of atoms and molecules, in chemical reactions an energy exchange occurs.
The chemical compounds they house in the bonds of atoms that compose them energy, which we know as chemical energy. Chemical reactions are usually expressed through equations, where on the left the reagents and to the right the products, linking both parts with a right arrow if the reaction is reversible or a back and forth arrow if it is a reversible reaction.
When the quantities or proportions in which the reactants react and the products are obtained are indicated, we speak of stoichiometric reactions.
When the energy of the products is less than that of the reactants that originated them, a net energy release, which can manifest itself in different ways, including heat, light, and electricity. These types of reactions are known as reactions exothermic. Chemical reactions endothermic, Conversely, they absorb energy.
The laws of chemical reactions
In chemical reactions the weight laws are fulfilled, of this the most important is the law of conservation of mass or Lavoisier's law, formulated by this chemist in 1774, which postulates that in every chemical reaction the mass of the reactants is equal to the mass of the products.
It was Dalton who completed the explanation of this law some years later, by indicating that in a chemical reaction the number of atoms does not vary when comparing the reactants with the products, only their organization changes, so the mass of is conserved.
Another important parameter in chemical reactions is their reaction speed, since not all take the same time to produce. The reaction rate is defined as the amount of product that appears per unit of time or the amount of reagent that disappears per unit of time.
Although each reaction has a different speed, certain factors can cause this tendency to increase or decrease: the contact surface and the temperature are some of them.
The catalysts They are substances that increase the speed of a reaction, without modifying its structure, metals often play this role.
See also: Examples of Catalysts and their functions
Examples of chemical reactions
Chemical reactions occur continuously in nature, in the human body, in factories, in effluent treatment plants, etc. Some of them are listed below:
- Combustion
- Substitution
- Addition
- Elimination
- Oxidation
- Reduction
- Acid-base reactions
- Oxygenation
- Transamination
- Chlorination
- Carbonylation
- Nitrosilation
- Peroxidation
- Photolysis of water
- Sulfation
- Carbonation
- Ozonation
- Esterification
- Hydrogenation
- Acetylation
It can serve you: Examples of Chemical Phenomena
