Stanislao Cannizzaro and the Foundation of the Periodic System
The Princeton Section of the ACS is joining with the Rutgers University Chemistry Department to present a public lecture on Wednesday April in celebration of the 150th anniversary of the Periodic Table. The venue is the CCB building at Rutgers, Piscataway. There is no dinner but a delectable Italian desert will be served.
The North Jersey Section is supporting this event with a modest grant and invites its members to attend.
The event is free, but advance registration is required for planning purposes. Note: There is link below to a registration form at the Princeton University website. Warning: that page (like apparently every page at that website) currently takes 20-30 seconds to load, so be patient! The other registration form is for parking and is at the Rutgers site, so it should be normal.
Announcing . . .
Meeting of the Princeton ACS Section
In conjunction with
Department of Chemistry and Chemical Biology
In Celebration of the International Year of the Periodic Table
Wednesday, April 17, 2019
Professor Heinz D. Roth, Rutgers University
“Stanislao Cannizzaro and the Foundation of the Periodic System”
CCB Auditorium, Rutgers University, New Brunswick, NJ -
Mixer 5:45 pm; Seminar 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 meeting will be held at Rutgers University,
321 Bevier Road, Piscataway, NJ, CCB Auditorium. The seminar is free, however reservations are
requested. (Please note that there will not be a dinner following the lecture.)
Should you have questions, please contact .
Italian treats will be served prior to lecture in the CCB Atrium at 5:45PM.
Parking: Complimentary parking is available in lot 54