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Period: 770 BCE to 476 BCE
Chemistry in ancient times
The Chinese believed that metal, wood, water, earth and fire made up matter, something that changed thanks to great philosophers and intellectuals. -
500 BCE
Prehistoric Times
The discovery of fire, led them to make their food more airship and without pathogens, in addition to the realization of weapons with metals. -
Period: 201 to 900
Alchemy
Techniques were found for the transmutation of metal, the elixir of life was sought and new substances were discovered like nitric acid. -
Period: to
Iatrochemistry
It was focused on medicine and finding cures for discomforts. -
Period: to
Phlogiston period
It was believed that if a material was flammable, it had a lot of phlogiston. -
The Sceptical Chymist
Robert Boyle publishes The Sceptical Chymist, a treatise on the distinction between chemistry and alchemy. It has some of the earliest modern ideas of atoms, molecules, and chemical reactions. -
Boyle's law
Robert Boyle proposes Boyle's law, which was based on the description of the behavior of gases, specifically about the relationship between pressure and volume. -
Hydrogen
Henry Cavendish discovered hydrogen as a colorless, odourless gas that burns and can form an explosive mixture with air. -
Combustion
Antoine Lavoisier recognizes and names oxygen, and recognizes its role in combustion. -
Charles's law
Jacques Charles proposes Charles's law that describes the relationship between temperature and volume of a gas. -
Chemical battery
Alessandro Volta devised the first chemical battery, thereby founding the discipline of electrochemistry. -
Water
Joseph Louis Gay-Lussac discovers that water is composed of two parts hydrogen and one part oxygen by volume. -
Avogadro's law
Amedeo Avogadro proposes Avogadro's law, that equal volumes of gases under constant temperature and pressure contain equal number of molecules. -
Biomolecules
William Prout classifies biomolecules into their modern groupings: carbohydrates, proteins and lipids. -
Synthesis of urea
Friedrich Woehler accidentally synthesized urea from inorganic materials.
Discovered by Alexander Fleming. In September 1928, he noticed the growth of a fungus during experiments, but made his discovery public until 1929. -
Concept of absolute zero
Lord Kelvin establishes the concept of absolute zero, the temperature at which all molecular motion ceases. -
Beer's law
August Beer proposes Beer's law, which explains the relationship between the composition of a mixture and the amount of light it will absorb. -
Vacuum Tube
Heinrich Geissler creates the first vacuum tube. -
Chemical structure
Friedrich Kekulé looks at the chemical structure of benzene, bringing the study of molecular structure to chemistry. -
Telluric helix
Alexandre-Émile Béguyer de Chancourtois publishes the telluric helix, an early, three-dimensional version of the periodic table of the elements. -
Early version of the periodic table
Lothar Meyer develops an early version of the periodic table, with 28 elements organized by valence. -
Avogadro's number
Johann Josef Loschmidt determines the exact number of molecules in a mole, later named Avogadro's number. -
The Periodic Table of the Chemical Elements
Dmitry Mendeleev formulated the periodic table to make easier to identify the known elements, without memorize the characteristics of each one. There were several scientists involved and they noted that certain chemicals were helpful in performing painless surgeries. -
Cathode Rays
William Crookes created a glass vacuum tube which had a zinc sulfide coating on the inside of one, a metal cathode put in the other end and a metal anode in the shape of a cross. When electricity was run through the tube, an image of the cross appeared and the zinc sulfide glowed. That made him to do the hypothesis that there must have been rays coming from the cathode which caused the zinc sulfide to fluoresce and the cross to create a shadow. -
Electrolytes
Svante Arrhenius develops ion theory to explain conductivity in electrolytes. -
The Proton
Eugene Goldstein discovered positive particles by using a tube filled with hydrogen gas. The positive particle had a charge equal and opposite to the electron. The positive particle was named the proton. -
X-rays
They were discovered accidentally by Wilhem Roetgen. At the time of the discovery, Roetgen was conducting experiments with cathode ray radiation. It was then that he noticed that the rays are capable of being fixed on opaque black paper. -
Pitchblend
Henri Becquerel was studying the fluorescence of pitchblend when he discovered a property of the pitchblend compound. -
The Electron and Its Properties
J.J. Thomson concluded that all atoms have negative charge and he renamed the cathode rays electrons. -
Nuclear model of the atom
Hantaro Nagaoka proposes an early nuclear model of the atom, where electrons orbit a dense massive nucleus. -
Ammonia
Fritz Haber and Carl Bosch develop the Haber process for making ammonia from its elements, an important fact in industrial chemistry with deep consequences in agriculture. -
Plastics
Leo Hendrik Baekeland invented bakelite, one of the first commercially successful plastics. -
Mass of the Electron
Robert Millikan discovered the mass of an electron by introducing charged oil droplets into an electrically charged field. -
Organization of the elements
Antonius van den Broek proposes the idea that the elements on the periodic table are more properly organized by positive nuclear charge rather than atomic weight. -
Isotopes
Frederick Soddy proposes the concept of isotopes, that elements with the same chemical properties may have differing atomic weights. -
Protons within a Nucleus
Henry Moseley attempts to use x-rays to determine the number of protons in the nucleus of each atom but his try was unsuccessful because the neutron hadn't been discovered yet. -
Chemical equation
Jean Beguin publishes the Tyrocinium Chymicum, an early chemistry textbook, and in it draws the first-ever chemical equation. -
Valence bond theory
Gilbert N. Lewis publishes "The Atom and the Molecule", the foundation of valence bond theory. -
Chemical thermodynamics
Gilbert N. Lewis and Merle Randall publish Thermodynamics and the Free Energy of Chemical Substances, first modern treatise on chemical thermodynamics. -
Exclusion principle
Wolfgang Pauli develops the exclusion principle, that states that two electrons around no a single nucleus may have the same quantum state. -
Quantum chemistry
Fritz London and Walter Heitler apply quantum mechanics to explain covalent bonding in the hydrogen molecule, which marked the birth of quantum chemistry. -
The Neutron
James Chadwick discovers the neutron. -
Artificial Radioactive Elements
Irene Curie and Frederic Joliot-Curie discovered that radioactive elements could be created artificially in the lab with the bombardment of alpha particles on certain elements. -
Nylon
Wallace Carothers leads a team of chemists who invent nylon, one of the most commercially successful synthetic polymers in history. -
Helium
Pyotr Kapitsa, John Allen and Don Misener produce supercooled helium, the first zero-viscosity superfluid. -
Chemical bonding
Linus Pauling publishes The Nature of the Chemical Bond, a compilation of decades worth of work on chemical bonding. It explains covalent bonding and ionic bonding through electronegativity and resonance. -
Manhattan Project
Below the football field at the University of Chicago, the United States developed the very first working nuclear fission reactor. The Manhattan Project was in process. -
Nuclear magnetic resonance
Felix Bloch and Edward Mills Purcell develop the process of nuclear magnetic resonance, an analytical technique important in elucidating structures of molecules, especially in organic chemistry. -
Structure of DNA
James D. Watson and Francis Crick propose the structure of DNA, opening the door to the field of molecular biology. -
Noble gases
Neil Bartlett synthesizes xenon hexafluoroplatinate, showing for the first time that the noble gases can form chemical compounds.
