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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 ...

Atomic Number and Mass Number of Elements: Atoms are the building blocks of matter. They are responsible for the format of all living and non-living things. Understanding their molecular structure and ...

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 ...

Since the turn of the century, six new chemical elements have been discovered and subsequently added to the periodic table of elements, the very icon of chemistry. These new elements have high atomic ...

One hundred years ago the Harvard University chemist Theodore William Richards was awarded the 1914 Nobel Prize in Chemistry for his accurate determination of the atomic weights of many elements. This ...

University of Nottingham’s chemistry professor Martyn Poliakoff says that most chemists don’t know the atomic number of most elements and that it’s a pain to look in the periodic table. That’s why ...