All matter and therefore everything around us is made up of molecules. In turn, molecules are formed by atoms joined together. The combination of atoms can produce many types of molecules. There are millions of different molecules: some are part of our body, others are for industrial use, there are also those that are consumed as food, in addition to the various possibilities within the universe . Molecule
The atoms that exist to form molecules are not infinite. In fact, it is estimated that there are more than 100 atoms different in relation to their size and that the combination between them is what produces one type or another of molecules, an issue that has been much studied in the field of chemistry .
The representation of molecules
Based on more than one hundred types of atoms existing in nature and classified in the periodic table of elements, molecules can be represented by a sphere model or by a sphere and bar model. Its representation is relevant, as it allows us to have the image of each molecule and better understand its composition. Molecule
Pure and mixed substances
Pure substances are composed of only one type of molecule. In turn, these substances can be classified by the same element (for example, N2 indicates two nitrogen atoms and O2 refers to two oxygen atoms). On the contrary, pure substances can be a compound (for example, hydrogen sulfide represents H2S as it is formed by one atom of sulfur and two of hydrogen or water, which as we know H2O is one atom of oxygen and two of hydrogen ). In this way, pure substances can be simple or composite. Molecule
Substances in nature can also mix together creating new structures and this happens by combining two or more substances, for example, by mixing water and oil or water and salt. Consequently, the mixture is an entire matter formed from several molecules. In the field of chemical industry there is a need to create mixtures of all types through different processes. These procedures are applied in different sectors: in cosmetics, in the pharmaceutical industry, in the food sector , industrial engineering, etc.
The idea of mixture can be understood in two ways: homogeneous and heterogeneous mixing. Homogeneous ones are made up of different substances, but it is not possible to tell them apart quickly (for example, tap water is made up of water and a series of ions and other smaller molecules). In the heterogeneous mixture, it is possible to differentiate its components at a glance (for example, placing a mixture of water and sand in a container). Molecule
