Atoms

DEVELOPMENT OF PARTICLE MODDLE OF MATTER

  • Democritus
    460 BCE

    Democritus

    hypothesised that all matter is made up of tiny discrete particles called atoms which are too small to be seen
  • Aristotle
    450 BCE

    Aristotle

    Hypothesised that matter has a continuous composition that can be broken down into smaller and smaller pieces
  • John Dalton

    John Dalton

    Suggested that all matter is made up of small discrete particles that are solid
  • Robert Brown

    Robert Brown

    observed that small pollen grains which are dead suspended in water were constantly moving randomly in all direction it is called as brownian motion.
  • Albert Einstine

    Albert Einstine

    explained that the dead pollen grain were moving because they were being bombarded by the moving water particles.