Chemistry is the science that studies the composition, properties and changes that matter experiences .
In other words, chemistry is the discipline that is responsible for analyzing and understanding how substances are composed and how they are transformed.
Like other sciences, chemistry is based on the scientific method to achieve its objective.
The word khemeia is the ancestor of the chemical word . Khemeia means ‘art of extracting juices’, and comes from the Greek khumos.
In Arabic, khemeia was transformed into al-khimiya , which was adopted by the Europeans as alchemy. Those who were dedicated to alchemy were called alchemists. The word alchemy was transformed into chemistry .
What does chemistry study?
When the ice melts or a nail rusts, there is a change in matter. When we pour salt into a glass of water, there is also a change in matter. Matter is everything we see and all changes in matter are studied by chemistry.
Chemistry seeks to understand the structure of atoms and how they come together to form molecules. Also how molecules react and the concentration or quantity of molecules in a space.
Whether a gas rises or falls depends on its chemical properties. The energy released by the compounds and the speed at which they react are problems of chemistry. Concepts such as pH and acidity, surface tension, catalysis, ions, electrolytes and temperature are the day to day of chemists.
Branches of chemistry
- Analytical chemistry : is dedicated to the analysis of substances. Analytical chemists usually work in production and quality control in industries.
- Biochemistry : chemical reactions at the molecular level in living organisms are the objective of the study of biochemistry.
- Inorganic chemistry : focuses on the study of inorganic compounds, that is, all those compounds where carbon is not part of its constitution.
- Organic chemistry : includes the study of carbon and all its compounds. Organic chemists work in industries as diverse as pharmaceuticals and the oil industry.
- Physicochemistry : addresses the physical properties and behavior of matter through models and theories.
Chemistry is in many products of daily life. Chemists use chemical reactions to produce drugs, plastics, fabrics, among other things. The process of producing chemical compounds is called chemical synthesis .
In industries, quality control is an application of chemistry. Analyzing the purity of materials, intermediate products and final products to ensure that they meet the conditions demanded by the public is important.
Another application of chemistry is in environmental chemistry . Air and water pollution are problems addressed by government or private agencies. These perform chemical analyzes to determine the amount of contaminating compounds present in a given sample and thus be able to take protective measures.
In the area of health , chemistry has many applications. For example, the level of sugar (glucose) in the blood is measured by chemical reactions. The same goes for many other blood compounds, such as cholesterol and hormones. This is done to determine the health status of a person.
Chemistry is also involved in the development of medicines and nutritional supplements. Many of the medicines that we use and know are chemical products.
Like the other sciences, chemistry is not a completely independent science. The applications of chemistry in physics and biology have been very useful, so much so that physicochemistry and biochemistry exist as branches of chemistry.
Importance of chemistry
Our day to day is full of chemistry: inside our body, in our skin and everything around us.
To know chemistry is to be able to discover why at one moment we feel sick to our stomach, why our hands are clean after using soap, and even why we can eat an egg after boiling it.
There is hydrochloric acid in our stomach, whose chemical formula is HCl. Hydrochloric acid in the stomach helps digest food. When we have a burning in the stomach, which we call heartburn, many times we take a substance, milk of magnesia, which helps to neutralize the hydrochloric acid. Milk of magnesia is a base, magnesium hydroxide.
When we use soap to wash our hands or bathe, we are using a surfactant. This surfactant is a chemical that is attracted to water and fats. Therefore, a foam is formed that helps to release grease from dirt. The same goes for laundry detergents.
In the kitchen
The kitchen is one of the places in the house where chemistry reigns. A raw egg is almost transparent and gelatinous, but when we cook it, it becomes white and hard. This is due to chemical reactions of egg proteins by heat.
Chemistry is also very important in the behavior of people. Some psychological problems are due to changes in chemicals in the brain. Even falling in love implies a change in the chemistry of the body!
Brief history of chemistry
The first chemists were the alchemists who were looking for a way to transform iron into gold. The first book of chemistry was published in 1597 and showed the preparation of hydrochloric acid, ammonium sulfate and aqua regia.
In the sixteenth century the foundations of chemistry were established with the development of metallurgy and the use of minerals as medicines .
From alchemy to chemistry
In the seventeenth century, alchemy was losing importance and became the chemistry of the eighteenth century.
Antoine Laurent Lavoisier (1743-1794) explained the chemistry of combustion. He owes the law of conservation of matter.
The English chemist John Dalton (1766-1844) established the law of multiple proportions and formulated the first atomic theory.
Start of organic chemistry
The term “organic” was coined by Jöns Jacob Berzelius (1779-1848) to describe the substances coming from living beings, such as olive oil or sugar.
Chemistry in the 19th century
By 1830, 55 different elements were known. Julius Lothar Meyer (German chemist, 1830-1895) and Dimitri Mendeleyev (Russian chemist, 1834-1907) each developed their own versions of the periodic table .
The laws of thermodynamics were applied to chemical reactions and thermochemistry arose thanks to Josiah William Gibbs (1839-1903). Gibbs is credited with the concepts of free energy and chemical potential.
Synthesis of plastics
In 1869 celluloid was created, the first synthetic plastic. Neoprene was synthesized for the first time in 1932.
Radioactivity and its uses
Marie Sklodowska Curie (1867-1934) together with her husband Pierre Curie(1859-1906) discovered radioactivity. Thanks to the radioactive isotopes, chemical reactions could be determined in many biological processes in the 20th century.
Nowadays, chemists look for less harmful techniques for the environment, produce biofuels and generate alternative energies.