Papers Monthly

Chapter 5 Review

5.1
o Early Models of the Atom
o Democritus
 Greek teacher who lived in the 4th century B.C.
 Was the first to suggest the existence of particles, atoms
 Believed these structures were indivisible and indestructible.
 His ideas were not useful in explaining chemical behavior.
• Lacked experimental support
o John Dalton
 The modern process of discovery regarding atoms began with him.
 Was an English school teacher
 Unlike Democritus, Dalton performed experiments to test and correct his atomic theory.
 Dalton's atomic theory
• All elements are composed of tiny invisible particles called atoms
• Atoms of the same element are identical. The atoms of any one element are different from those of any other element.
• Atoms of different elements can physically mix together or can chemically combine with one another in simple whole-number ratios to form compounds
• Chemical reactions......

Approximate Word Count: 935
Approximate Pages: 4 (260 words per double-spaced page)