History of Chemistry
Five Historical Periods related to development of Chemistry
1) Practical Arts – 600 B.C. (ancient to present in some places)
Chemical Processes were based on experiences
No theoretical basis or understanding of chemical principles but they knew how to
do many chemical processes such as:
Preparation of dyes and medicines
Manufacture of pottery
Production of metals from ores
2) Greek – 600 B.C. to 300 B.C.
Considered theoretical aspects of chemistry
Two ideas:
a) Everything made of earth, fire, air, water, ether (Plato and others)
b) Matter is made up of atoms (Democritus 5th Century B.C.)
Wrong idea won out and with it the idea of the transmutation of matter
(convert lead to gold through some chemical process - WRONG )
3) Alchemy – 300 B.C to 1650 A.D.
Greek philosophy combined with Egyptian crafts
Combined chemical processes with astrology, mysticism, and Greek ideas
Goals of Alchemy:
1. Transmutation of base metals such as lead into gold
2. Find elixir of life (make people immortal)
4) Phlogiston – 1650 to 1790 (Wrong Idea)
Thought heat was a substance called phlogiston that was released by burning
wood ----> ashes + phlogiston (heat as substance)
5) Modern Chemistry – 1790 to present day
Antione Lavoisier his work formed the beginning of modern chemistry
published first real chemistry text Elementary Treatise on Chemistry in 1789
He used quantitative experimentation (such as weighing before and after reaction)
and showed gases involved in combustion
wood + oxygen ----> ashes + gases + energy
Modern chemistry makes connection between experiment and theory
Experimental observation <---- ----> theory
John Dalton an English School teacher in 1808 reintroduced the ancient idea of
Democritus - Atoms are the building blocks of nature!
Chemical reactions involve rearrangement of atoms but atoms are not created or
destroyed - This idea of mass not changing is also called “Conservation of Mass”
Chemistry is concerned with structure and transformations of matter on an atomic level.
Atoms come together to form compounds and compounds can break apart into atoms or
be combined to form new compounds.
Main areas of Chemistry:
Organic – compounds of carbon (some exceptions CO2 CO considered inorganic)
Inorganic – compounds that do not include carbon
Analytical – composition of matter and mixtures (what is there and how much)
Physical – applies ideas of math and physics to chemistry
Biochemistry – chemistry of living things (from bacteria to humans)
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