-
500 BCE
The Alchemists
The Alchemists where around from 500BC to 1700AD, they discovered a substance that would change common metals into sliver and gold. -
428 BCE
Plato
Plato was around in 428BC, Plato came up with the elements, -
400 BCE
Democritus
Democritus was around in 400BC, Democritus came up with the theory that matter is made from small indestructible units called atoms. -
Robert Boyle
Robert Boyle talked about the of atoms existing, and that elements are composed of corpuscles. -
Antone Lavoisier
Lavoisier showed and proved the conservation of matter, he proved that matter can neither be destroyed nor created. -
John Dalton
John Dalton proposed compounds are atoms from different elements combined together, he also made the billiard ball model, and said that atoms where identical and also had the same mass. -
Billiard Ball Model
John Dalton invented this model he believed that atoms where solid spheres, so he used hard wooden spheres to model his theory. -
Amedeo Avogadro
Amedeo Avogadro found out that equal volumes of gases at the same temperature and pressure contains equal number of molecules. -
Dmitri Mendeleev
Dmitri Mendeleev created the Periodic Table as we know it. -
JJ Thompson
JJ Thompson determined the charge to mass ratio of electrons, he made the plum pudding model, which had negatively-charged electrons embedded within a positively-charged as he called it "soup." -
Plum Pudding Model
Discovered by JJ Thompson this model has electrons surrounded by a volume of positive charge, he proved it by negatively charged plums and positively charged pudding that's why it was named that. -
Pierre and Marie Curie
Pierre and Marie Curie identified and studied radioactive elements, Marie and Pierre discover Radium, and Polonium. -
Albert Einstein
Albert Einstein proved the existence of atoms through mathematics and started the equivalence of energy and mass through the theory of special relativity. -
Robert Millikan
Robert Millikan found the charge of electrons with an experiment called oil drop. -
Ernest Rutherford
Ernest Rutherford was part of the Solar system model with Bohr which was his student, he discovered the atom is mostly empty space. -
Solar System Model
The Solar System Model was invented in 1913, by Rutherford, and Neil Bohr. It was meant to show how electrons are arranged in an aligned circular orbits around the nucleus. -
Neils Bohr
Neils Bohr explained the atomic structure theory and helped his professor Rutherford with the Solar System Model, which is that outer orbit of atoms can hold more electrons than inner orbit. -
Henry G. J. Mosely
Henry Mosely found out the atomic number and the number of protons in an element. -
Erwin Schrodinger
Erwin Schrodinger used math equations to find where the electron is moving, known as the quantum mechanical model of atoms. -
Electron Cloud Model
Erwin Schrodinger created this model shows a specific area where an electron is mostly likely to be. -
Werner Heisenberg
Werner Heisenberg discovered that a particles momentum and position cannot be both known exactly, he won a Nobel prize in 1932. -
James Chadwick
James Chadwick discovered the Neutrons in an atom, and he won a Nobel Piece prize in 1935.
