Set of atoms that make up a small part of a substance
For both Physics and Chemistry, a molecule is a set of atoms, whether the same or different, that are linked by chemical bonds which constitute the minimum portion of a substance that can be separated without its properties being altered. The case that the atoms are identical occurs, for example, in oxygen that has two atoms of this element, or they may be different, as in the case of the water molecule, which has two atoms of hydrogen and one of oxygen..
It could also be said that the molecule is that smallest particle that exhibits all the physical and chemical properties of a substance.
Distinctive features of molecules
Molecules are formations that are found in constant motion, a situation known as molecular vibrations, which in turn can be tension or bending and meanwhile, the atoms will stay together, united thanks to the fact that they share or exchange electrons.
On the other hand, molecules can possess electric charge, a situation called ion-molecule, or failing that, be neutral.
A good part of the substances that we know best and that we even consume are made up of molecules, such is the case of water and sugar.
Element approached from various sciences
Molecules arouse great interest from various disciplines, including especially physics, chemistry, biology, among others.
Meanwhile, the various branches of chemistry will deal with some specific aspects of molecules.
Organic Chemistry or Carbon Chemistry It is a part of chemistry that deals with analyzing those molecules composed of carbon and that also form carbon-carbon or carbon-hydrogen covalent bonds. Secondly, inorganic chemistry focuses on the study of the formation and structure of those elements and inorganic compounds. Then we find the organometallic chemistry which is responsible for chemical compounds that have a bond between a carbon atom and a metal atom.
Biochemistry It is the part of chemistry that has the task of studying living things at the molecular level. In this way, it will not only analyze the molecules that make up cells and tissues, but it will also deal with their main chemical reactions such as digestion, photosynthesis, among others.
For their part, physical and quantum chemistry are responsible for studying the properties and reactivity of molecules.
It should be noted that those molecules that are composed of the repetition of a unit and that have a high molecular weight are considered macromolecules or polymers.
The molecular formula
The description of the molecular structure is something very common when talking about molecules and that is why there is an agreed modality when doing it, such is the case of the molecular formula.
The aforementioned formula is composed of symbols of the elements that make up the molecule in question and also by the number of atoms that will be indicated in the subscripts, among the best known cases we can cite as an example that of water, a formula that is written like this H2O, or the case of ammonia which is formulated as follows: NH3. This way of formulation in the case of simple molecules, while for complex molecules the aforementioned chemical formula is not enough and then it is necessary to use a graphic formula, type scheme, in which the different functional groups present are noted.
