Atomic Structure

By alevac
  • 400

    Democritus

    Democritus
    Democritus reasoned that matter must be made of small particles that were indivisible and therefore named them atomos.

  • Lavoiser

    Lavoiser
    French chemist made measurments of a chemical change in a sealed container. He discovered the Law of Coinservation of Mass which is when mass before equals mass after. Matter cannot be created or destroyed.

  • Proust

    Proust
    Obsered that the composotion of water is always 11% hydrogen and 89% oxygen by mass. He also discovered law of definite proportion which is a constiant make-up.

  • Rutherford

    Rutherford
    Rutherford discovered the plum pudding model after doing the gold foil experiement

  • Milikan

    Milikan
    Did the oil drop experiement and concluded the mass of one electron is 1/1840 the mass of a proton- essentially the electron has no mass

  • Chadwick

    Chadwick
    provided the exixtence of the neutron

  • Thomson

    Thomson
    physicist J.J. Thomson discovered the electron and proposed a model for the structure of the atom. Thomson knew that electrons had a negative charge and thought that matter must have a positive charge. His model looked like raisins stuck on the surface of a lump of pudding.

  • Dalton

    Dalton
    He had a theory. Dalton believed matter is composed of tiny, indivisible particles known as atoms. Also that atoms of the same element are identical and atoms of any one element are different from those of another element. Reactions occur when atoms are separated from one another, joined, or rearranged. But matter cannot be created or destoyed. This is the Law of Cionservation of Mass.