Periodic Table Timeline Teacher Sheet

Periodic Table Timeline Teacher Sheet Photo Credit: Clipart.com


The purpose of this lesson is to introduce and focus on the early history of the periodic table. Students should use information from A Brief History of the Development of Periodic Table to complete a timeline. This sheet provides key dates, facts, figures, and events for the timeline. The answers to the remaining questions can be found in the body of the lesson.

Periodic Table Timeline
Students should fill in the blanks with the correct dates, facts, and figures. 

1649    —        Hennig Brand discovered phosphorus.

1829    —        Johann Dobereiner discovered the halogen triad and the alkali metal triad.

1862    —        The first periodic table was created by de Chancourtois. He assembled the table by

classifying chemical elements in an order based on their periodicity of chemical and

physical properties.

1864    —        John Newlands published his own version of the periodic table and developed the Law

of Octaves.

1869    —        Dmitri Mendeleev published his periodic table, eventually becoming the “father of the

periodic table.”

1870    —        Lothar Meyer published his version of the periodic table (after Mendeleev).

1895    —        Lord Rayleigh discovered argon, a new gaseous element that was chemically inert.

1898    —        William Ramsey helped to establish the “zero” group (for “zero valency”) and predicted

the future discovery of the element neon.

1911    —        Ernest Rutherford established that “the nuclear charge on a nucleus was proportional

to the atomic weight of the element.”

1911    —        A. van den Broek established that the atomic weight of an element was approximately

equal to the charge on an atom. This charge became the “atomic number” by which

periodic table elements are classified.  

1913    —        Henry Moseley discovered the isotopes of elements. This discovery established that

“the properties of the elements varied periodically with atomic number,” not atomic

weight, which had been previously accepted under periodic law.

1940    —        Glenn Seaborg discovered plutonium and the transuranic elements from 94 to 102.

His findings represented the last (and most recent) changes to the periodic table.


This teacher sheet is a part of the The History of the Atom 3: The Periodic Table lesson.

Did you find this resource helpful?