Atomic theory scientists timeline

By OthmaneEljoufri
  • 460 BCE

    Democritus

    Democritus
    The exact date of Democritus’s birth is unknown but it is assumed to be around 460 BCE in Abdera. He theorized that there were 2 different kinds of reality, atoms and void. He believed atoms are infinite in number, size and solid in shape. He theorized that they move in an infinite void and repel each other. He thought that atoms would form clusters because tiny hooks would catch each other. Democritus however did not experiment. He only based his theories off of observations he made.

  • Antoine Lavoisier

    Antoine Lavoisier
    Lavoisier contributed to the discovery of combustion and the element oxygen. He found that oxygen made up 20% of the atmosphere. He made the theory of mass conservation. Lavoisier used a giant magnifying glass to evaporate a diamond in a closed jar. When the diamond evaporated the glass weighed the same. He believed that sulfur was an element because it couldn’t be broken down anymore.

  • John Dalton

    John Dalton
    Dalton contributed the atomic theory. He theorized that all forms of matter are made of atoms. He also contributed a law that was named Dalton’s Law.

  • Robert Millikan

    Robert Millikan
    Millikan determined that electric charge carried by 1 electron. He did oil drop experiments to prove this.

  • Ernest Rutherford

    Ernest Rutherford
    Rutherford theorized the nuclear structure of an atom. He fired alpha particles into gas atoms to see if the deflected which they did proving atoms have a nucleus. He also won a Nobel prize in chemistry and was made a knight.

  • Albert Einstein

    Albert Einstein
    Einstein mathematically proved the existence of atoms. He also proved liquids are made of molecules in random non stopping motion. He showed that when light energy strikes atoms in the metal, the quanta force the atoms to release electrons.

  • Erwin Schrödinger

    Erwin Schrödinger
    Schrödinger described the behavior of electrons within atoms could be explained by treating them like waves. He took Bohr’s model further. He also used math to calculate position of electrons.

  • James Chadwick

    James Chadwick
    Chadwick assisted Rutherford in learning about atom’s nucleus and how atomic weight works. He fired alpha particles into atom to prove this. He was knighted for his work.