Chemical reactions. Types, examples and simulations

Types of chemical reactions

A chemical reaction can be classified into different types, depending on the nature of the reactants and products, and the way in which the transformation is carried out. Some of the most common types are:

Synthesis reactions or combination reactions

In the synthesis reactions, also called combination reactions, two or more reactants combine to form a single product. For example, the synthesis of water from hydrogen and oxygen.

Decomposition reactions

A single reactant is split into two or more products. For example, the decomposition of hydrogen peroxide into water and oxygen.

Substitution or displacement reactions

One element or functional group of a reactant is replaced by another element or functional group. For example, the reaction of an acid with a metal to form a salt and release hydrogen.

Oxidation-reduction reactions

A transfer of electrons occurs between the reactants, and may involve the gain or loss of electrons. For example, the oxidation of iron in the presence of oxygen to form iron oxide.

Precipitation reactions

In precipitation reactions, a solid is formed from aqueous solutions. These reactions occur when two solutions containing soluble salts mix and form an insoluble compound, known as a precipitate. A common example is the reaction between silver nitrate and sodium chloride, which results in the formation of solid silver chloride.

Acid-base reactions

In these reactions, an acid donates protons (H⁺) and a base accepts protons. This type of reaction is fundamental in many areas, including industrial and biological chemistry. An everyday example is the neutralization of hydrochloric acid in the stomach with antacids, which contain bases such as sodium bicarbonate.

Combustion reactions

A compound reacts with oxygen to produce carbon dioxide, water and the release of energy in the form of heat. For example, the combustion of hydrocarbons in engines.

Each type of chemical reaction has specific characteristics. For example, synthesis reactions tend to be exothermic, while decomposition reactions tend to be endothermic.

Examples of chemical reactions in everyday life

Chemical reactions are present in many aspects of our daily lives.

Photosynthesis

Photosynthesis is a synthesis reaction where plants produce glucose and oxygen from carbon dioxide and water with the help of sunlight.

Hydrocarbon combustion

Another example is the combustion of hydrocarbons in car engines, an oxidation-reduction reaction in which fuel reacts with oxygen to produce carbon dioxide and water, releasing energy in the form of heat.

Reactions in cooking

We also find decomposition reactions in cooking, such as when baking a cake in the oven decomposes baking soda into carbon dioxide and water, which helps the cake rise.

Reactions in the human body

Acid-base reactions are present in our body, such as the neutralization of hydrochloric acid in the stomach by bicarbonate in the intestine. Another fundamental example is the reaction of cellular respiration. During respiration, cells convert glucose and oxygen into carbon dioxide, water and energy. This process is essential for the production of energy that our body needs to function.

Cleansing products

Precipitation reactions are common when we mix certain solutions to clean lime from pipes, forming solids that can be easily removed.