IYPT Timeline of Elements

The Radioactive Elements

2019 International Year of the Periodic Table

Although the radioactive elements uranium and thorium were discovered early in the history of the elements — 1789 and 1828, respectively, years before the advent of the Periodic Table — radioactivity itself was unknown until 1896 when Henri-Antoine Becquerel (1852-1908) in Paris found that uranium could expose photographic plates, even when protected by black opaque paper. The renowned Marie Curie (1867-1934) promptly made a study of all elements (that were known at that time) and determined that only two were radioactive — uranium and thorium.

The Creation of the Periodic Table

2019 International Year of the Periodic Table

In 1789 Lavoisier turned the concept of “element” on its head when he proposed that water was a compound and that hydrogen, oxygen, carbon, sulfur, iron, copper, and 25 other substances were the true elements. Author: James L Marshall, Professor Emeritus, University of North Texas, Denton, Texas

Unveiling an international masterpiece

The Timeline of Elements interactive exhibit and Mendeleev Mosaic

Chem 13 News and the Department of Chemistry are excited to announce the unveiling of the final pieces of our Timeline of Elements Project! Both the Timeline of Elements interactive exhibit and the accompanying Mendeleev Mosaic will be highlighted during an official unveiling ceremony on October 26, 2019. Author: Victoria Van Cappellen, University of Waterloo, Waterloo, Ontario

Spectroscopy

2019 International Year of the Periodic Table

The alchemists had known since the 1500s that salts could impart various colors to a flame. In the 1700s Andreas Sigismund Marggraf (1709-1782) demonstrated that sodium salts could be differentiated from potassium salts by the former’s yellow color and the latter’s purple hue. Author: James L Marshall, Professor Emeritus, University of North Texas, Denton, Texas

Berzelius’ World

2019 International Year of the Periodic Table

In previous chapters we have seen how chemistry has evolved in stages. First was the world of the ancients with their concept of the four elements — fire, earth, water and air. Author: James L Marshall, Professor Emeritus, University of North Texas, Denton, Texas

Humphry Davy and the Voltaic Pile

2019 International Year of the Periodic Table

Historically, the distinction between sodium and potassium was not made easily. Only gradually was it recognized that there was a difference between “plant alkali” (potash, potassium carbonate), obtained from the ashes of plants, and “mineral alkali” (soda, sodium carbonate), found in salt flats and evaporated seawater. Author: James L Marshall, Professor Emeritus, University of North Texas, Denton, Texas

IYPT 2019 Timeline of Elements poster

To celebrate International Year of the Periodic Table (IYPT 2019) as print copy subscribers, you have received a Timeline of Elements poster with this, our last print copy of Chem 13 News magazine. Author: Jean Hein, Chem 13 News Editor, University of Waterloo, Ontario

An Introduction to the Philatelic Table of the Elements 2.0

Larry French from St. Lawrence University, Canton, New York describes his updated version of the Philatelic Table of the Elements. This new version was presented at the spring 2016 American Chemical Society Meeting to mark the International Year of the Periodic Table (IYPT 2019). This version of the table has been updated to include the four most recently named elements. In addition, a handful of stamp selections have been altered in order to broaden topical coverage in ways that might enhance potential uses in the classroom.

True elements — Lavoisier and Phlogiston

2019 International Year of the Periodic Table

The stage was now set for a giant leap in the understanding of chemistry. A vast amount of knowledge had been accumulated during the previous several thousand years. Author:James L Marshall, Professor Emeritus, University of North Texas, Denton, Texas

The Miners

2019 International Year of the Periodic Table

Modern science depends upon both theory (basic science) and technology (practical applications). Likewise, progress during the Middle Ages depended upon both theory and technology — as the alchemists were plodding along with their secret recipes and cryptic writings, the practical miners were advancing their techniques for extracting the metals from the ores for spears, plowshares and ornaments. Author: James L Marshall, Professor Emeritus, University of North Texas, Denton, Texas

Marie mosaic

As inspiration for our mosaic here is another collaborative chemistry mosaic we found that appeared on the front cover of the 2011 September issue of Nature Chemistry (Volume 3 Issue 9). This cover was a celebration of the International Year of Chemistry and the 100th anniversary of the awarding of the Nobel Prize in Chemistry to Marie Curie. In this issue, Michelle Francl considers how the representation of women in science has changed since Curie's day.

The Ancients and the Alchemists

2019 International Year of the Periodic Table

[This series is a companion to our International Year of the Periodic Table project — Timeline of Elements and Mendeleev Mosaic. Time periods from our timeline project will be featured highlighting the historical and scientific advancements resulting in the discoveries of the elements of that period. Jim Marshall researches the history of the discovery of the elements. Author: James L Marshall, Professor Emeritus, University of North Texas, Denton, Texas

2019 International Year of the Periodic Table update

In January 2019 we start to celebrate the International Year of the Periodic Table of Elements. Hopefully those who are designing elements for the Timeline of Elements project have already started!

2019 International Year of the Periodic Table Timeline of Elements

YES! We are doing another collaborative project! If you missed out on participating in our 2011 Periodic Table Project, this is your opportunity to have your students celebrate and be part of a worldwide initiative.