Atom theories

  • Demócrito
    460 BCE

    Demócrito

    He called these infinitesimally small fragments of matter atoms, which means "indivisible." He suggested that the atoms were eternal and could not be destroyed.
  • Aristóteles
    384 BCE

    Aristóteles

    He believed that matter was continuous and could be divided endlessly into smaller portions. Aristotle thought that all nature was composed of four elements: Earth, Air, Water and Fire.
  • John Dalton

    John Dalton

    It is based on the following statements: - Matter is made up of atoms, which are indivisible and indestructible particles. - All atoms of the same chemical element are equal in mass and properties and different from the atoms of any other element.
  • Thomson

    Thomson

    Thomson thought that electrons were immersed in a positively charged substance that counteracted the negative charge of electrons, since atoms have a neutral charge. Something similar to having a jelly with raisins floating inside. For this reason his atomic model was known as the raisin pudding model.
  • Jean Perrin

    Jean Perrin

    He modified Thomson's model by first suggesting that the negative charges are external to the "Pudding"
  • Rutherford

    Rutherford

    Thomson's model presented a static and solid atom. The model proposed by Rutherford suggests that the positive charge of the atom is concentrated in a stationary nucleus of great mass, while the negative electrons move in orbits around the nucleus, linked by the electrical attraction between opposite charges.
  • Niels Bohr

    Niels Bohr

    Quantified model of the atom proposed in 1913 by Danish physicist Niels Bohr, to explain how electrons can have stable orbits around the nucleus and why atoms had characteristic emission spectra. In addition, Bohr's model incorporated ideas taken from the photoelectric effect, explained by Albert Einstein in 1905.
  • Sommerfeld

    Sommerfeld

    With the help of Albert Einstein's theory of relativity he made the modifications to Bohr's model.
  • Erwin Schrödinger

    Erwin Schrödinger

    Schrödinger suggested that the movement of electrons in the atom corresponded to the wave-particle duality, and consequently, electrons could move around the nucleus as standing waves.