Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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Sub Image1:Atoms and Molecules
1) Atoms and Molecules
2) Macro to Micro Structures 3) Energetics and Dynamics 4) Theory and Practice in Chemical Systems 5) Chemical Design 6) The Chemistry of Life 7) Chemistry and the Environment 8) Chemistry at the Interface

Unit 1.5 Atomic Theory
The development of early models of the atom is discussed, beginning with atomism 400 B.C., to models of Greek philosophers, to Dalton’s first atomic theory.
Video program cues: 31:40-33:40

The early understanding of the atom


  • A timeline of atomic theory from Democritus to the 1950’s with links to important scientists and discoveries.

History of the atomic theory

"[Democritus:] Everything was composed of atoms, which moved randomly in a vacuum, in a void. They collided into each other by chance. This was the absolute negation of Aristotle's idea that everything had a purpose as divinely ordained [the theory of the Four Elements]."

Dr. Hugh Salzburg
Chemistry Historian


Giunta, C.J. (2001) 'Using History to Teach Scientific Method: The Role of Errors', 'Journal of Chemical Education, Vol. 78, No. 5, pp: 623-627.

Leary, J.J. and Kippeny, T.C. (1999) ‘A Framework for Presenting the Modern Atom’, 'Journal of Chemical Education, Vol. 76, No. 9, pp: 1217-1218.

Proceed to Unit 1.6 arrow

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