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 ...

A team led by nuclear physicists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) has reported the first direct measurements of the mass numbers for the nuclei of two ...

Scientists made the first direct, definitive measurement of the weight, also known as the mass number, for two superheavy nuclei. Now, scientists know the weight (total number of protons) of ...

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 ...