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Joint PACS, NJACS and Rutgers IUPAC Event – April 17
April 17 @ 5:45 pm
Meeting of Rutgers Department of Chemistry and Chemical Biology and the North Jersey and Princeton ACS Sections
In conjunction with
In Celebration of the International Year of the Periodic Table
(Hosted by Professor Spencer Knapp, firstname.lastname@example.org)
Wednesday, April 17, 2019
Professor Heinz D. Roth, Rutgers University
“Stanislao Cannizzaro and the Foundation of the Periodic System”
CCB Auditorium, Rutgers University
Mixer 5:45 pm; Lecture 6:30 pm
The “modern” periodic tables published by Lothar Meyer in 1864 and Dmitry Mendeleev in 1865 use atomic weights as one of the key ordering principles. Stanislao Cannizzaro deserves credit for deriving a collection of these data.
In the mid-1800s, there was no generally accepted nomenclature. Relating Dalton’s atoms, Gay-Lussac particles, or Avogadro’s molecules and half-molecules presented a problem – how could atoms or Avogadro’s molecules, indivisible by definition, be split? Cannizzaro based his approach on four fundamental hypotheses, viz., Dalton’s atomic theory, Gay-Lussac’s law of combining volumes (1808), Avogadro’s molecular hypothesis (1811), and Dulong and Petit’s hypothesis of atomic heat capacity (1819).
Cannizzaro unified the essence of these hypotheses. Based on known vapor densities, heat capacities, and stoichiometries of a large number of systems, he re-formulated Avogadro’s hypotheses. Differentiating between the terms atoms and molecules, and replacing Avogadro’s symbols, e.g., H1/2 and H, with H and H2, he derived internally consistent atomic and molecular weights of simple elements and compounds. He published his approach in Nuovo Cimento (1858), presented his approach at the Karlsruhe Congress (1860), and distributed reprints of his work. Among the participants of the Congress were Meyer and Mendeleev, and it is in their work that Cannizzaro’s approach came to full fruition.
The Seminar will be held at Rutgers University, Department of Chemistry and Chemical Biology, CCB Auditorium, 123 Bevier Rd, Piscataway, NJ 08854 at 6:30 pm. The seminar is free and open to the public, however reservations are requested. Italian treats will be served prior to lecture in the CCB Atrium at 5:45 pm. (There will not be a dinner following the lecture.)
Complimentary parking available in lot 54 ( Map and directions) and lot 51B Lot 51 B map and directions), however pre-registration of your vehicle is required. Click here to register your car in advance.
If you have questions, contact email@example.com.