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Democritus' Theory of Matter
Democritus came up with a theory that the universe is made of two different elements. He aslo states that all matter are composed of tiny particles called atoms, atoms are indestructible, differ in size, weight, temperature, arrangement. Solids are composed of larger atoms than liquids. 465BC -
Antoine-Laurent Lavoisier's Law of Conservation
Antoine-Laurent proposed that matter cannot be created or destroyed. Antoine also suggest the rearrangement of matter in reactions. -
John Dalton Atomic Theory
He looked at almost every scientist or philosopher in history who had any conception of atoms whatsoever. After he completed his research, he compiled it into what we call Dalton's Theory. His theory contained 6 parts:
matter is composed of extremely small particles called atoms
atoms are indivisible and indestructable
atoms of a given element are identical in size, mass, and chemical properties
atoms of specific elements are different thatn those -
Robert Millikan Oil Drop Experiment
Robert Millikan performed an "oil-drop" experiment, determined the charge of one electron and using the known mass-charge ratio, was able to calculate the mass on one electron (9.11x10^-28g) -
Niels Bohr's "Bohr Model"
Bohr studied the structure of an atom. He suggested that electrons didn't spiral into the nucleus, but orbit in different levels. Bohr atomic model states when atoms absorb or emit radiation when the electrons switch to a different state. -
Joseph Protust's Law of Definite Proportions
The law states that the ratio of elements in a compound is always the same/constant. He also hinted at the 'lego'ness of matter; he believed that matter could be put together in certain patterns to make bigger, different, unique matter.
