What classifications of chemical reactions do you know? What are the signs they are based on?

What classifications of chemical reactions do you know? What are the signs they are based on? Show examples of reactions of the selected types and their equations.

To understand all the variety of chemical reactions, you need to know their classification. In inorganic chemistry, the following types of chemical reactions are distinguished:
1) Compound reactions – chemical reactions, the product of which is the formation of a new complex chemical from several simple or complex substances. For example, the reaction of combining carbon with oxygen, as a result of which carbon dioxide is formed: C + O2 = CO2;
2) Decomposition reactions – a type of chemical reaction, as a result of which several new chemical substances are obtained from one complex substance. For example, the decomposition reaction (electrolysis) of water: 2H2O = O2 + 2H2;
3) Substitution reactions – chemical reactions during which the atoms of a chemical element are replaced by atoms of a less electronegative chemical element in a complex substance. An example is the substitution of potassium atoms for iron atoms in iron hydroxide: 2K + Fe (OH) 2 = 2KOH + Fe;
4) Metabolic reactions – these chemical reactions take place with the participation of two complex substances. For example, the reaction between hydrochloric acid and silver nitrate: HCl + AgNO3 = HNO3 + AgCl.
As can be seen from the examples and descriptions above, this classification is carried out taking into account these reaction products and reagents.
There is also a classification of chemical reactions based on the release (exothermic) and absorption (endothermic) energy (heat – Q), as well as on the basis of reversibility (reversible and irreversible) chemical reactions. Examples of exo- and endothermic reactions:
1) 2H2 + O2 = 2H2O + Q (exothermic);
2) N2 + O2 = 2NO – Q (endothermic).