CHEM.5.A

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The student is expected to explain the development of the Periodic Table over time using evidence such as chemical and physical properties;
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Knowledge and Skills Statement

Science concepts. The student understands the development of the Periodic Table and applies its predictive power.

a characteristic of a particular substance that can be observed during or after a chemical reaction; a quality that can be established only by changing a substance's chemical identity

 data that supports a hypothesis or an argument and is observable through the senses or technology

an organizational chart of all the known elements on Earth, organized based on the physical and chemical properties of each

 observable characteristic of matter that can be used to identify particular materials

Research

Scerri, Eric R. “The Evolution of the Periodic System.” Scientific American (2011). https://www.scientificamerican.com/article/the-evolution-of-the-periodic-system/

Summary:  The Periodic Table shows patterns in the chemical properties of elements. Elements were originally grouped into triads by similarity. Scientists then realized that elements could be a part of two different triads and be compared in two directions. Mendeleev’s system recognized a pattern in the property of elements. This article explains the history and progression of the Periodic Table and how its pattern can be used to predict the properties of elements.

Research

n.a. "How the Battle for the Periodic Table was Won." Nature 613, no.7944 (2023): 413. doi:10.1038/d41586-023-00083-4

Summary:  A century ago, the discovery of hafnium secured the periodic table - but only thanks to scientists who stood up for evidence at a time of global turmoil. The find secured not only the periodic table's legacy but also the future of chemistry. Hafnium also came to represent a hard-won victory against those determined to undermine evidence-based discovery. One hundred years on from hafnium's discovery, the periodic table remains both robust and relevant, even at a time when reams of data on an element can be accessed at the click of a mouse. The table offers, at a glance, a reference to how an element might behave in a chemical reaction, and clues to its similarity to other elements in a group.