Sam Harrelson

Here is the notesheet we covered (partly) in class on Tuesday. We’ll finish this when we get back on next Monday…

“And the atoms move continuously for all time, some of them falling straight down, others swerving, and others recoiling from their collisions… and these motions have no beginning, since the atoms and the void are the cause.”
Epicurus (341-270 BCE) “Letter to Herodotus”

“We might as well attempt to introduce a new planet into the solar system, or to destroy one already in existence, as to create or destry a particle of hydrogen.”
John Dalton (1766-1844), English chemist and physicist, A New System of Chemical Philosophy

I. Atom’s History
a. Greeks
b. Chinese
c. Aristotle

II. Thinkers on the Atom
a. Thomas Harriot
b. Isaac Newton - “it seems probable to me, that God in the Beginning form’d Matter in solid, massy, hard impenetrable, moveable Particles.”
c. Gottfried Wilhelm Leibniz - “When I was a young man, I also gave in to the notion of a vacuum and atoms; but reason brought me into the right way,”
d. Dalton

III. Dalton’s Life
a. Education
b. Professorship
c. Science

IV. Dalton and Atoms
a. Lavoisier
b. all matter, not just gases, consists of those small particles he called atoms.
c. atom weights

V. Dalton Weighs the Atom
a. “Thus a train of investigation was laid for determining the number and weight of all chemical elementary particles which enter into any sort of combination one with another.”
b. “An inquiry into the relative weights of the ultimate particles of bodies is a subject, as far as I know, entirely new. I have lately been prosecuting this inquiry with remarkable success.”
c. Ratios of weights in compounds
d. Classifying based on weight
e. atoms can neither be created nor destroyed

“Dalton’s atomic theory allowed chemistry to become an exact science. The importance of making numerically precise measurements of chemical processes had been clear enough to others; but without an underlying theory of the elements, these numbers were like measurements of the depth of a river or the number of ants in a colony 0 they did not reveal anything about the fundamental constitution of the system.
-Philip Ball, “The Ingredients: A Guided Tour of the Elements.”

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