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Students use the terms isotope, atomic number, mass number, and atomic mass. Atomic Theory: Structure of the Atom: Students use the terms isotope, atomic number, mass number, and atomic mass to ...

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...

Creating mnemonic phrases can help you remember the order of elements, especially for the first 20 elements or specific groups. These phrases are general and are available on other free online sources ...