Periodic Table
http://genius.com/1894437/Todd-beard-periodic-table/The-heart-of-chemistry
In the beginning
Frederich Wöhler (1800-1882)
Synthesized urea from salts
(by accident)
So?
Wikipedia
Soon thereafter
Ira Remsen (1846-1927)
Hired to JHU by Daniel Coit Gilman
Formed the chemistry department
Appointed JHU president, nurtured
Development as a research university
His ashes are in Remsen Hall
Wikipedia
Why should you care?
WÖHLER trained
Limpricht who trained
Fittig who trained
REMSEN who trained
Norris who trained
Ashdown who trained
Woodward who trained
Breslow who trained
Grubbs who trained
Swager who trained
TOVAR
… who is now training you in a sense
Models for atomic structure
J. J. Thomson
(1856-1940)
Discovered electrons
1897
“plum pudding model”
Electrons embedded
In nuclear pudding
Hantaro Nagaoka
(1865-1950)
“Saturn model”
1904
Electrons around
the nucleus
Niels Bohr
(1885-1962)
Electrons quantized
In energy levels
1913
Wikipedia
Periodic Table
http://genius.com/1894437/Todd-beard-periodic-table/The-heart-of-chemistry
History of “tetravalent carbon”
Louis Pasteur (1822-1895)
Studied crystals formed from wine
(more on this later)
He described the molecules within these
crystals as being part of an
“irregular tetrahedron”
“in spite of his genius, Pasteur was sometimes
Unfair, combative, arrogant, unattractive in
attitude, inflexible and even dogmatic”
Wikipedia
History of “tetravalent carbon”
August Kekulé (1829-1896)
“Verwandtschaftseinheiten” or “affinity units
as precursors to “bonds”
… and carbon had 4 of them.
Published in 1857
More on Kekulé later … (dreams of snakes, etc.)
Wikipedia
http://html.rincondelvago.com/friedrich-august-kekule.html
History of “tetravalent carbon”
Archibald Scott Couper (1831-1892)
He proposed a similar theory before Kekulé
And gave the paper to his lab advisor (Wurtz)
Who didn’t read or otherwise delayed publication
Lines for bonds:
Kekulé received the credit, and Couper had
a nervous breakdown and was institutionalized
Wikipedia
http://www.chemheritage.org/discover/online-resources/chemistry-in-history/
themes/molecular-synthesis-structure-and-bonding/kekule-and-couper.aspx
History of “tetravalent carbon”
Alexander Butlerov (1828-1886)
He proposed carbon’s tetrahedral arrangement
“a known spiritualist ... Connections with the dead,
seances, premonitions, the irrational …”
“Perhaps Butlerov’s capacity to accept what could
not be proved helped in his proposal …”
Wikipedia
M. M. Green Organic Chemistry Principles in Context
Periodic Table
http://genius.com/1894437/Todd-beard-periodic-table/The-heart-of-chemistry
Models for covalent bonding
Gilbert N. Lewis (1875-1946)
“Lewis dot” structures (1916)
Bonds consisting of two shared electrons
Acid/base theory (1923, more later)
Coined the term “photon” (1926)
Nominated 35 times for the Nobel Prize
Found dead in lab with HCN gas
Wikipedia
Early depictions of Lewis’ ideas
(1902)
Wikipedia and Journal of the American Chemical Society 1916, 38, 762-785.
G. N. Lewis, Valence (1923)
“I take it that a monograph of this sort belongs
to the ephemeral literature of science. The studied care
which is warranted in the more slowly moving branches of
science would be out of place here. Rather with the pen
of the journalist we must attempt to record a momentary
phase of current thought, which may at any instant
change with kaleidoscopic abruptness.
It it therefore not unlikely that some of the things
said in this book may soon have to be unsaid …
Periodic Table
http://genius.com/1894437/Todd-beard-periodic-table/The-heart-of-chemistry
Models for bonding and structure: VSEPR
Ronald Gillespie
(1924 - )
Ronald S Nyholm
(1917-1971)
Wikipedia
Models for bonding and structure: MO/VB
Robert S. Mullikan
(1896-1986)
Coined the word
“orbitals”
MO theory
Wikipedia
John C. Slater
(1900-1976)
Atomic orbitals
Hybridization
“valence bond”
theory
Linus Pauling
(1901-1994)
Hybridization
of orbitals
“valence bond”
theory
Generation of sp3 orbitals
http://chemwiki.ucdavis.eduTheoretical_ChemistryChemical_
BondingValence_Bond_Theory/Hybridization
Generation of sp3 orbitals
http://chemwiki.ucdavis.eduTheoretical_ChemistryChemical_
BondingValence_Bond_Theory/Hybridization
Periodic Table
http://genius.com/1894437/Todd-beard-periodic-table/The-heart-of-chemistry