-
-
Aristotle disliked the idea of the atom and believed that every substance was made from proportions of air, earth, fire and water.
-
-
-
-
-
He stated his law of definite proportion stating that compounds will have the same proportions of elements in them.
-
Concluded that atoms of the same element are the same but differ from atoms of different elements based on atomic weight. Also he states that atoms of one element can combine with another element to form a compound. Also states that atoms cant not be created, divided into smaller particles.
-
-
Becquerel showed that the rays emitted by uranium caused gases to ionize and that they differed from x-rays in that they could be deflected by magnetic fields.
-
Found that atoms contained particles which were called electrons. Found that the electrons were negatively charged.
-
Found that the action of an electron, angular momentum, bound into an atom or molecule is limited but, an unbound electron does not show limited energy levels,
-
-
Rutherford suggested that there was a dense positively charged nucleus being orbited by small negatively charged electrons.
-
Millikan discovered the mass of an electron is one thousandth of the mass of even the smallest atom.
-
-
Bohr Model;
States that electrons travel in small orbits around the atom’s nucleus. -
He suggested that electrons could move like waves and not only particles, thus answering several holes in the Bohr model.
-
Was accredited of finding an electron around the atom. Does not show exact but a probable location.
-
He worked out the uncertainty principle which was an equation for the principle the by hitting an electrom with a gamma ray you could measure its location or momentum, but the more precisely one was measured the less precisely the other is measured.
-
-
The Discovery of the Neutron;
Proved that the atomic nucleus contained a neutral charged particle called the Neutron. -
-
-
-
-
States that between atoms lies empty space; that atoms are indestructible; have always been, and always will be, in motion; that there are an infinite number of atoms, and kinds of atoms, which differ in shape, and size.
