2019 International Year of the Periodic Table Timeline of Elements

The Periodic Table represents more than 5,000 years of human discovery. We marked the 2019 International Year of the Periodic Table (IYPT) with a worldwide collaboration that chronicles this amazing story in a timeline illustrated by students from 118 schools in 28 countries.

Learn about the discovery of the elements through several resources on this site, all linked below:

Explore the eight time periods, which include an abridged history of the challenges and breakthroughs that contributed to the modern periodic table 150 years ago.
Watch the periodic table "grow" with each time period in our latest video.
Click on the poster image for the interactive PDF, which links each element tile to its time period and detailed history. The image gallery offers enlarged views of the artwork, organized by atomic number.

Watch video on YouTube

Navigating the interactive poster and companion website

Look for the following navigation features that will help you move seemlessly through time:

Click on the top image to access the interactive PDF (accessible) version of the poster. From there, click on any element to be taken directly to its image and description.
To search for an element by atomic number, visit our image gallery.
Each element is linked to its website description - click on the website image of the element again to see a fully enlarged image of the artwork.
Each time period webpage includes an image of the poster showing which elements are included, so you know where you are in the timeline. Clicking these images will also take you to the interactive PDF.
Using your browser's back button will take you back to your previous spot.
We've added navigation buttons and links within time periods so that you can move faster up, down and between time periods. The "Go back to Main Page" button will bring you back here.
Watch the periodic table "grow" with each time period in our latest video above.

Note: There has been a correction to the original poster. Thorium (Th, 90) was moved from the decade 1875-1884 to 1825-1834 and Thulium (Tm, 69) was shifted from 1865-1874 to 1875-1884. The website, interactive pdf and downloadable poster are all updated to reflect this change.

The on-campus mural and interactive exhibit

The Timeline of Elements has also been turned into a full-wall mural and interactive exhibit located in the basement of the Science Teaching Complex (STC) on the University of Waterloo main campus.

The mural, measuring 16m (52.5 ft) long by 3.3m (10.8 ft) high, occupies the entire wall between rooms 0060 and 0050. Interactive displays include touchable native elements, reconstruction of the original voltaic pile (i.e. battery) and a spectrometer visitors can use to identify a variety of elements.

Why 2019 and Why a timeline?

The United Nations General Assembly proclaimed 2019 as the International Year of the Periodic Table of Chemical Elements (IYPT 2019). The goal “in proclaiming an International Year focusing on the Periodic Table of Chemical Elements and its applications, the United Nations has recognized the importance of raising global awareness of how chemistry promotes sustainable development and provides solutions to global challenges in energy, education, agriculture and health.”

This year coincides with the 150th anniversary of Dmitry Mendeleev’s published periodic table in 1869.

Chem 13 News readers will remember our 2011 Periodic Table Project, which produced a wall mural, free mobile app and classroom posters. To celebrate the Year of the Periodic Table we decided to take a different approach to the table and deconstruct it into the years the elements were discovered. Our goal was to have chemistry students from around the world join together to create an original and imaginative version of the Timeline of Elements focused on their discovery.

How this project came together

Teachers were asked to apply on behalf of their students to design an artwork for one assigned element. With more than 200 applications from over 29 countries, we held a lottery, taking into consideration special reasons if a school would like a particular element.

In the end, all the elements were assigned to 118 schools from 28 countries, including every province and territory in Canada. See the participants with their artwork.

Teachers are encouraged to make their own classroom timeline or periodic table to celebrate 2019. If you do, please send us photos as we would love to post them on our website celebrating the International Year of the Periodic Table.

Our sponsors and contributors

We'd like to thank the following sponsors for their financial support of this project:

University of Waterloo Faculty of Science
The Department of Chemistry
Chem 13 News
The Chemical Institute of Canada Chemical Education Fund for sponsoring the production and delivery of two posters to all high schools across Canada.
3M Canada for creating the Timeline of Elements mural in the Science Teaching Complex at the University of Waterloo.

Bringing 118+ pieces of artwork into a meaningful and educational piece has truly been a joint effort. It’s thanks to the vision, talent, patience – and yes, persistence – of each member of this team, that we were able to make the Timeline of Elements poster, companion website, and interactive wall mural a reality.

Jean Hein, former Editor, Chem 13 News
Heather Neufeld, Manager, Science Outreach
Corina McDonald, Museum Curator, Earth Sciences Museum
Victoria Van Cappellen, Web Administrator, Department of Chemistry
Joy Roasa and Jaime Simons, our amazing Waterloo Co-op students

We would also like to thank

Kathy Jackson, Chem 13 News Secretary, Department of Chemistry, and
Melissa Martinez, Communications Design Specialist, Creative Services

Receive a print quality PDF of the poster

Subscribe to Chem 13 News online and receive a free high resolution printable PDF of the poster!

More questions? E-mail Chem 13 News (chem13news@uwaterloo.ca).