Timeline of chemistry

This timeline of chemistry lists important works, discoveries, ideas, inventions, and experiments that significantly changed humanity's understanding of the modern science known as chemistry, defined as the scientific study of the composition of matter and of its interactions.

Known as "the central science", the study of chemistry is strongly influenced by, and exerts a strong influence on, many other scientific and technological fields. Many historical developments that are considered to have had a significant impact upon our modern understanding of chemistry are also considered to have been key discoveries in such fields as physics, biology, astronomy, geology, and materials science.

Pre-17th century

Prior to the acceptance of the scientific method and its application to the field of chemistry, it is somewhat controversial to consider many of the people listed below as "chemists" in the modern sense of the word. However, the ideas of certain great thinkers, either for their prescience, or for their wide and long-term acceptance, bear listing here.

;c. 450 BC: Empedocles asserts that all things are composed of four primal roots (later to be renamed ''stoicheia'' or elements): earth, air, fire, and water, whereby two active and opposing cosmic forces, love and strife, act upon these elements, combining and separating them into infinitely varied forms.

;c. 440 BC: Leucippus and Democritus propose the idea of the atom, an indivisible particle that all matter is made of. This idea is largely rejected by natural philosophers in favor of the Aristotlean view (see below).

;c. 360 BC: Plato coins term ‘ elements’ (''stoicheia'') and in his dialogue Timaeus, which includes a discussion of the composition of inorganic and organic bodies and is a rudimentary treatise on chemistry, assumes that the minute particle of each element had a special geometric shape: tetrahedron (fire), octahedron (air), icosahedron (water), and cube (earth).

;c. 350 BC: Aristotle, expanding on Empedocles, proposes idea of a substance as a combination of ''matter'' and ''form''. Describes theory of the Five Elements, fire, water, earth, air, and aether. This theory is largely accepted throughout the western world for over 1000 years.

; c. 50 BC: Lucretius publishes '' De Rerum Natura'', a poetic description of the ideas of atomism.

;c. 300: Zosimos of Panopolis writes some of the oldest known books on alchemy, which he defines as the study of the composition of waters, movement, growth, embodying and disembodying, drawing the spirits from bodies and bonding the spirits within bodies.

;c. 800: ''The Secret of Creation'' (Arabic: ''Sirr al-khalīqa''), an anonymous encyclopedic work on natural philosophy falsely attributed to Apollonius of Tyana, records the earliest known version of the long-held theory that all metals are composed of various proportions of sulfur and mercury. This same work also contains the earliest known version of the '' Emerald Tablet'', a compact and cryptic Hermetic text which was still commented upon by Isaac Newton.

;c. 850–900: Arabic works attributed to Jābir ibn Ḥayyān (Latin: Geber) introduce a systematic classification of chemical substances, and provide instructions for deriving an inorganic compound (sal ammoniac or ammonium chloride) from organic substances (such as plants, blood, and hair) by chemical means.

;c. 900: Abū Bakr al-Rāzī (Latin: Rhazes), a Persian alchemist, conducts experiments with the distillation of sal ammoniac (ammonium chloride), vitriols (hydrated sulfates of various metals), and other salts, representing the first step in a long process that would eventually lead to the thirteenth-century discovery of the mineral acids.

;c. 1000: Abū al-Rayhān al-Bīrūnī and Avicenna, both Persian philosophers, deny the possibility of the transmutation of metals.

;c. 1100–1200: Recipes for the production of ''aqua ardens'' ("burning water", i.e., ethanol) by distilling wine with common salt start to appear in a number of Latin alchemical works.

;c. 1220: Robert Grosseteste publishes several Aristotelian commentaries where he lays out an early framework for the scientific method.

;c 1250: The works of Taddeo Alderotti (1223–1296) describe a method for concentrating ethanol involving repeated fractional distillation through a water-cooled still, by which an ethanol purity of 90% could be obtained.

;c 1260: St Albertus Magnus discovers arsenic and silver nitrate. He also made one of the first references to sulfuric acid.Vladimir Karpenko, John A. Norris(2001)
Vitriol in the history of Chemistry
Charles University

;c. 1267: Roger Bacon publishes ''Opus Maius'', which among other things, proposes an early form of the scientific method, and contains results of his experiments with gunpowder.

;c. 1310: Pseudo-Geber, an anonymous alchemist who wrote under the name of Geber (i.e., Jābir ibn Hayyān, see above), publishes the . This work contains experimental demonstrations of the corpuscular nature of matter that would still be used by seventeenth-century chemists such as Daniel Sennert. Pseudo-Geber is one of the first alchemists to describe mineral acids such as or 'strong water' (nitric acid, capable of dissolving silver) and or 'royal water' (a mixture of nitric acid and hydrochloric acid, capable of dissolving gold and platinum).

;c. 1530: Paracelsus develops the study of iatrochemistry, a subdiscipline of alchemy dedicated to extending life, thus being the roots of the modern pharmaceutical industry. It is also claimed that he is the first to use the word "chemistry".

;1597: Andreas Libavius publishes ''Alchemia'', a prototype chemistry textbook.

17th and 18th centuries

;1605:Sir Francis Bacon publishes ''The Proficience and Advancement of Learning'', which contains a description of what would later be known as the scientific method.

;1605:Michal Sedziwój publishes the alchemical treatise ''A New Light of Alchemy'' which proposed the existence of the "food of life" within air, much later recognized as oxygen.

;1615:Jean Beguin publishes the '' Tyrocinium Chymicum'', an early chemistry textbook, and in it draws the first-ever chemical equation.

;1637:René Descartes publishes ''Discours de la méthode'', which contains an outline of the scientific method.

;1648:Posthumous publication of the book ''Ortus medicinae'' by Jan Baptist van Helmont, which is cited by some as a major transitional work between alchemy and chemistry, and as an important influence on Robert Boyle. The book contains the results of numerous experiments and establishes an early version of the law of conservation of mass.

;1661:Robert Boyle publishes ''The Sceptical Chymist'', a treatise on the distinction between chemistry and alchemy. It contains some of the earliest modern ideas of atoms, molecules, and chemical reaction, and marks the beginning of the history of modern chemistry.

;1662:Robert Boyle proposes Boyle's law, an experimentally based description of the behavior of gases, specifically the relationship between pressure and volume.

;1735:Swedish chemist Georg Brandt analyzes a dark blue pigment found in copper ore. Brandt demonstrated that the pigment contained a new element, later named cobalt.

;1754:Joseph Black isolates carbon dioxide, which he called "fixed air".

;1757:Louis Claude Cadet de Gassicourt, while investigating arsenic compounds, creates Cadet's fuming liquid, later discovered to be cacodyl oxide, considered to be the first synthetic organometallic compound.

;1758:Joseph Black formulates the concept of latent heat to explain the thermochemistry of phase changes.

;1766:Henry Cavendish discovers hydrogen as a colorless, odourless gas that burns and can form an explosive mixture with air.

;1773–1774: Carl Wilhelm Scheele and Joseph Priestley independently isolate oxygen, called by Priestley "dephlogisticated air" and Scheele "fire air".

;1778:Antoine Lavoisier