History of the Periodic Table of the Elements

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History of the Periodic Table of the
Elements (CHEM 1360) Part 1
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Democritus 460?-370? B.C. Proposed matter was
composed of indivisible particles he called
atoms
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Lucretius 95?-55? B.C. Roman poet and
philospher who attempted to explain sensory
appearances of matter on physical properties of
atoms
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Honey and milk are pleasant to the tongue. . .
. From smooth round atoms come those things which
touch Our senses pleasantly. . . .
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But wormwood and red gentian both are bitter. .
. .
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Little spurs projecting just a bit, to tease our
senses, To tickle rather than sting, like wine or
elecamphane. . . .
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Hard things. . . flint, iron, bronze. . . tight
knit, Must have more barbs and hooks to hold
them, Must be more interwoven, like thorny
branches. . . .
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Water must be composed of rounded particles. . .
. and salt atoms are roughened and pitted. . . .
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According to Lucretius, the properties of matter
observed by us depend on the physical behavior
and motion of atoms (while the atoms themselves
do not possess these properties). FOR EXAMPLE
Lemons are sour not because lemon atoms are
sour, but because lemon atoms are ragged
and scrape across the tongue. The saltiness of
ocean water is not due to salt atoms that taste
salty, but because salt atoms have pitted and
rough surfaces that rub on the tongue. In fact,
the rough salt atoms can be removed by filtering
through earth the rougher surface helps them
stick in earth.
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Aristotle (384-322 B.C.) believed in a primordial
substance that is the basis of all matter in the
universe.
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Change the qualities of wetness,
dryness, hotness, coldness
Earth
Fire
Primordial Matter
Air
The four elements of Aristotle result
Water
According to Aristotle, one form of matter can be
transmuted into another by simply changing the
qualities of the primordial matter.
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Tin
Bronze
Copper
As an example of Aristotles philosophy, we can
blend the quality of tin with the quality of
copper to obtain a new quality of bronze.
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Aristotles idea of primordial matter which could
be subtly varied by Nature was reinforced by
observations by miners. Silver, for example, can
be observed to grow into intricate forms proof,
it was thought, that metals are alive.
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Just as caterpillars can transmute into
butterflies, we see all of Nature is constantly
striving for perfection. Thus, all metals in the
bowels of the earth are evolving. . . .
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And we see the even basest of metals lead
slowly transforming in nature into the most
perfect metals of all gold.
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The contribution of Democritus and Lucretius was
the concept that matter is composed of tiny
particles which may look very strange indeed
and whose behavior on an atomic scale determined
how the matter was perceived and sensed by
us. The contribution of Aristotle was the idea
of primordial matter. This concept laid the
foundation for the dreams of alchemists who
aspired to duplicate Nature and transmute base
metals into gold, thereby discovering thousands
of new chemicals. After the true immutable
elements were discovered (Lavoisier, 1789),
Aristotles idea led, in the twentieth century,
to the discovery of the primordial matter of
protons, electrons, and neutrons and to the
realization that elements were not really
immutable after all.