Consider only the nucleus when you are concerned with isotopes. Electrons play no part in isotopes or the atomic mass, Figure 2. Only protons and neutrons contribute to the mass of an isotope.
Month: February 2019
Matter: Composition
Matter by Composition You can describe matter based on composition. This means you describe collections of matter based on what makes it up. The first kind of description refers to whether or not you want to describe a pure substance or mixture. Pure Substance…