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460 BCE
Democritus
Leucippus of Abdera, the philosopher, conceives of the atomic universe. His pupil is Democritus. -
Antoine Lavoisier
He became the first person to experiment with the atom -
John Dalton
John Dalton was born September 6, 1766 in the United Kingdom. -
Law of Conservation of Mass
The Law of Conservation of Mass was founded by Antoine Laurent Lavoisier. It states that in a chemical reaction, matter is neither created nor destroyed -
Law of multiple proportions
Dalton developed the law of multiple proportions. It states "'When two elements combine with each other to form two or more compounds, the ratios of the masses of one element that combines with the fixed mass of the other are simple whole numbers'. -
J.J. Thomson
J.J. Thomson was born December 18,1856 in Cheetham, Manchester. -
Max Planck
Max Planck was born April 23, 1858 -
Robert Andrews Millikan
Robert Andrews Millikan was born on the 22nd of March, 1868, in Morrison, Illinois. -
Ernest Rutherford
Ernest Rutherford was born August 30, 1871 in Nelson, New Zealand -
Marie Curie
Marie Curie was born November 7, 1867. -
Albert Einstein
Albert Einstein was born March 14,1879 in Ulm , Germany. -
Erwin Schrodinger
Erwin Schrodinger was born August 12, 1887 in Vienna -
Louis De Broglie
Louis De Broglie was born August 15,1892 in Dieppe, France. -
J.J. Thomson discovering electrons
j.j. discovered the electrons ( particles which are smaller than atoms and which have a negative charge ) -
Marie Curie Contribution
Curie discovered polonium and radium. She deduced that radioactivity does not depend on how atoms are arranged into molecules, but rather that it originates within the atoms themselves. -
Max Planck Contribution
Max Planck discovered the quantum theory . he assumed that energy was made of individual units or quanta -
Werner Heisenberg
Werner Heisenberg was born December 5, 1901 -
Thomas discovering a method for separating
Thomson discovered a method for separating different kinds of atoms and molecules by the use of positive rays -
Robert MIllikan Contribution
Robert Millikan determined the unit charge of the electron in 1909 with his oil drop experiment at the University of Chicago. -
Rutherford Contribution
Rutherford concluded that the atom was mostly made up empty space except for a dense central region which became known as a nucleus. -
Albert Einstein Contribution
Theory of Relativity was created. it explains the general case of any sort of motion. Einstein's theory was based on two key principles: The principle of relativity: The laws of physics don't change, even for objects moving in inertial (constant speed) frames of reference. -
Einstein wins Nobel Prize
Albert Einstein wins Nobel PRize in Physics in 1921 -
Millikan won a Nobel Prize
Robert Millikan won a Nobel Prize for Physics in 1923 -
Heisenberg contributions
he formulated a type of quantum mechanics based on matrix -
Schrodinger contribution
Erwin Schrodinger developed an “Electron Cloud Model” in 1926. -
Heisenberg Contribution
He proposed the " uncertainty relation " setting limits for how precisely the position and velocity of a particle can be simultaneously determined. -
Louis De Broglie wins Nobel Prize
Louis De Broglie wins the the Nobel Prize in Physics in 1929 -
Chadwick Contribution
Chadwick discovered the neutron in atom -
Schrodinger wins Nobel Prize
For this work he shared with Dirac the Nobel Prize for 1933.
