-
460 BCE
Democritus Is Born
Democritus is born in Abdera Greece in 460 BC -
Period: 430 BCE to 401 BCE
Democritus proposes an Atomic Universe
Democritus along with Leucippus prose that all humans are made of tiny particles called "Atomos", which is Greek for Uncutables -
370 BCE
Democritus Dies
Democritus dies in the year 370 BC of natural causes. -
Antoine Lavoisier Is Born
Antoine Lavoisier Is born in Paris, France, August 26, 1743 -
John Dalton Is Born
John Dalton is born September 6, 1766 in Cumberland, England -
Lavoisier Gains Admission to the Academy of Sciences in Paris
Instead of practicing Law like his father and grandfather he pursued research that got him accepted into the Academy of Sciences -
Lavoisier names carbon
Lavoisier and a group of chemists burned a diamond and charcoal in closed glass jars using a giant magnifying glass. Lavoisier noticed that even though the diamond/charcoal disappeared the jar maintained its weight and that diamonds and charcoal produce the same gas. He realized that diamonds and charcoal are different forms of the same element. He names this element carbon. -
Antoine Lavoisier obtains his liscense to practice science
-
Lavoisier states sulfer is an element
Lavoisier asserts that sulfur is an element after conducting experiments in which he concluded that it cannot be broken up further. -
Lavoisier names oxygen
Lavoisier coins the name oxygen for the element given off by mercury oxide. -
Lavoisier names hydrogen
Lavoisier coined the name ‘hydrogen’ for the gas which Henry Cavendish discovered I 1766. -
Antoine Lavoisier Dies
Lavoisier is executed during the French Revolution -
Dalton proposes his atomic teory
Dalton Proposed his atomic theory as part of a lecture in 1803. He theory states that atoms make up all matter, atoms are indivisible, atoms of different elements have different masses, atoms of the same element have identical properties, and atoms of different elements combine in fixed ratios when forming compounds. -
John Dalton Dies
John Dalton dies of a stroke on July 27, 1844 -
J. J. Thompson is Born
Thompson is born in Cheetham Hill, England on December 18, 1856. -
Max Planck is Born
Max Planck is born in Kiel, Germany on April 23, 1858. -
Marie Curie is Born
Marie Curie is born in Warsaw, Poland on November 7,1867 -
Robert Milikan is Born
Robert Millikan is born in, Morrison, Illinois, U.S., on March 22, 1868. -
Ernest Rutherford is Born
Ernest Rutherford is born in New Zealand on August 30, 1871 -
Albert Einstein is Born
Albert Einstein is born in Württemberg, Germany on March 14, 1879. -
Niels Bohr
Niels Bohr is born in Copenhagen, Denmark on October 7, 1885 -
Erwin Schrodinger is Born
Erwin Schrodinger is born in Vienna, Austria on August 12, 1887 -
James Chadwick is Born
James Chadwick is born in Manchester, England on October 20, 1891 -
Louis De Broglie is Born
Louis De Broglie is born in Dieppe France on August 15, 1892 -
Marie Curie Finds out other matter is radioactive
Curie studies thorium and figures out it is radioactive. -
Radium is Discovered
Marie Curie discovers radium in the summer of 1898 -
Planck's Radiation Law
Planck comes up with his radiation law to explain the spectral-energy distribution by a blackbody. -
Werner Heisenberg is Born
Werner Heisenberg is born in Würzburg, Germany on December 5, 1901. -
Theory of Relativity
Einstein comes up with the theory of relativity to expresses the fact that mass and energy are the same physical entity and can be changed into each other with the equation E=mc^2 -
Period: to
Rutherford and Geiger
Along with Geiger, Rutherford developed an electrical counter for ionized particles. It was used by Rutherford to precisely calculate Avogadro's number. -
Oil-drop Experiment
Millikan began a series of experiments to determine the electric charge carried by a single electron. Then he began measuring the course of oil droplets in a charged field. From this he was able to measure the electric force and magnitude of the electric field. By doing these experiments he proved radiation is of extraterrestrial origin. -
Gold-Foil Experiment
Rutherford and his co-workers performed with the gold-foil experiment and concluded that an atom is made up of mostly empty space. -
First use of mass spectrometer
Thompson discovers stable neon isotopes by channeling a stream of ionized neon through a magnetic and electric fields. Then he used deflection techniques to measure the charge to mass ratio. This was the first use of mass spectrometer -
Bohr' Atomic Model
In 1912 Bohr comes up with his version of the atomic model. -
De Broglie's atomic theory
He asserted that an electrons must move like a wave or a particle around atom with restricted motion. -
Quantum Mechanical Model
Schrodinger's take on the Bohr model with the addition of the mathematical equation to describe the behavior of the electrons movement. -
Uncertainty Principle
Heisenberg states that a particle’s momentum and position could not be measured at the same time. -
Discovery of the neutron
Chadwick bombarded beryllium with alpha particles.
After the bombardment he proposed that radiation is composed of particles with mass about equal to the proton but with no electrical charge. These are neutrons -
Marie Curie Dies
Marie Curie dies near Sallanches, France on July 4, 1934 -
Ernest Rutherford Dies
Ernest Rutherford dies in Cambridge, England on October 19, 1937 -
Thompson Dies
J. J. Thompson dies August 30, 1940 -
Max Planck Dies
Max Planck dies in Göttingen, Germany ,on October 4, 1947. -
Robert Milikan Dies
Robert Millikan dies in San Marino, California on December 19, 1953 -
Albert Einstein Dies
Albert Einstein dies on April 18, 1955 -
Erwin Schrodinger Dies
Erwin Schrodinger dies in Vienna, Austria on January 4, 1961. -
Niels Bohr Dies
Niels Bohr dies in Copenhagen, Denmark on November 18, 1962 -
James Chadwick Dies
James Chadwick dies in Cambridge, Cambridgeshire on July 24, 1974 -
Werner Heisenberg Dies
Werner Heisenberg Dies in Munich, West Germany in February 1, 1976. -
Cathode Ray Experiment
J. J. Thompson discovers the electron after one of his sessions with Cathode rays. He concluded that particles that made up the gases are universal. He calls them 'corpuscles' today they are known as electrons. -
Louis De Broglie Dies
Louis De Broglie dies in Louveciennes on March 19, 1987
