Download Guided Notes: The Atom

Guided Notes: The Atom
History of the Atom
Democritus- Greek philosopher; 400 BC
1st to use word “atomos” (means_______________________________)
Aristotle-refuted what Democritus said; all matter comes from “hyle”
Early Alchemists-1200-1500’s; tried to turn material into _________; kept chemistry alive;
recorded observations and experiments
John Dalton-late 1700’s-early 1800’s
Model of the Atom; Dalton’s Atomic Theory
J.J. Thomson-1896; discovered electrons using a cathode ray tube; ______
of atom
__________ model
Goldstein- late 1800’s discovered _______
Millikan-oil drop experiment; found quantity of charge on an _________: carries exactly
_____________ of charge, and mass is 1/1840 the mass of a proton
Rutherford-1910; __________________ experiment; model of the atom- discovered nucleus and
that the atom is mostly empty space
James Chadwick-1932 discovered the __________
Dalton’s Atomic Theory
4 Models of the Atom
1. All elements are composed of tiny invisible
particles called atoms
2. Atoms of the same element are identical. The
atoms of any one element are different from
those of any other element.
3. Atoms of different elements can physically
mix together or can chemically combine with
one another in simple whole-number ratios to
form compounds.
4. Chemical reactions occur when atoms are
separated, joined, or rearranged. Atoms of one
element, however, are never changed into atoms
of another element as a result of chemical
reaction.
Dalton’s
Atomic Model
Rutherford’s Model
1. Nucleus
2. Empty Space
JJ Thomson
Plum Pudding Model
Electron Cloud Model
-Accepted Today