What is chemistry?
Chemistry is the natural and experimental science that studies matter, its structure, properties, and composition. It also analyzes the transformation that matter undergoes through reactions, as well as its relationship with energy. Chemistry is considered one of the major contemporary sciences.
According to Jean-Marie Lehn, a supramolecular chemist and winner of the 1987 Nobel Prize in Chemistry, chemistry “is a science that aims not only to discover but also, and above all, to create, since it is the art of making matter complex.”
Chemistry’s evolution, as well as our understanding of it and its denomination as a science, has changed over time, and these are a few milestones in its history:
- Prehistoric period, when the first humans were interested in materials, making them, handling them, and using them for survival. What we today know as combustion responds to homo erectus‘s need to generate fire and heat.
- Greek antiquity, when the first philosophers presented hypotheses regarding matter based on observation and experimentation. The most valuable contribution from this era is in philosopher Abdera Democritus’s approach: he established that matter was composed of small particles called atoms.
- Eastern chemistry, which precedes what we know as modern chemistry. Around the year 1330, alchemists held mystical beliefs about the philosopher’s stone for transforming materials into gold while developing techniques, materials, and instruments now used in chemical laboratories.
- In 1661, Irishman Robert Boyle published The Skeptical Chemist. With this work, chemistry was unfettered from any subjective claims advanced by alchemists.
- From the eighteenth century on, chemistry began to be called a modern experimental science due to the development of more precise, verifiable techniques for measurement that gave way to the discovery of various phenomena. This was consecrated with the postulation of John Dalton’s atomic theory in 1983.
- 2011 was declared the International Year of Chemistry by the United Nations (UN).
What are the essential concepts associated with chemistry?
There are several basic concepts that are essential not only to study chemistry but to understand its complexity:
- Matter: everything that has mass and volume and is composed of particles, whether pure substances or mixtures.
- Atom: the basic, smallest unit of matter chemistry considers. Atoms have weight, volume, and electric charge. They are made up of an atomic nucleus surrounded by a set of electrons revolving around it.
- Subatomic particles: the particles that make up atoms and give them properties. There are three types: protons (positively charged), electrons (negatively charged), and neutrons (uncharged).
- Molecules: the union of two or more atoms with unique properties, which form compounds.
- Chemical element: a substance made up of a set of atoms that have the same number of protons in their nucleus. There are 118 chemical elements in the periodic table.
- Chemical compounds: substances consisting of more than one chemical element in the periodic table. Their main characteristic is that they have a chemical formula, such as water, for example, which is composed of hydrogen and oxygen.
What are the branches or disciplines of chemistry?
Chemistry is organized according to the type of material at hand. These include:
- Organic chemistry.
- Inorganic chemistry.
- Biochemistry, which studies the substances present in biological organisms.
- Physiochemistry, which studies the structure and energy load in chemical systems at the macroscopic, molecular, and atomic levels.
- Analytical chemistry, which analyzes samples of materials to understand their structure and composition through reactions.
How is chemistry applied to sustainability?
As we have seen, chemistry has played a significant role in the lives of human beings since the distant past, influencing our lifestyle and transforming our environment.
In sustainable industrial production, both for producing materials and for their processing and sale, the following are important:
- It makes producing fuels other than hydrocarbons possible, thus aiming to reduce environmental impact.
- It makes it possible to create new techniques for recycling materials.
- It makes it easier to manufacture much more resistant, economical, and ecological building materials.
- It helps develop compounds to eliminate pests in crops.