1.2 The nuclear atom

• Nucleus: protons + neutrons (nucleons), positively charged, dense

• Electrons: negatively charged, occupy space outside nucleus

• Use nuclear symbols to deduce protons, neutrons, and electrons in atoms and ions

• Same element, different numbers of neutrons

• Nuclear symbol: Z^A X (Z = protons, A = mass number)

• Calculate relative atomic masses from isotopic abundance

• Understand isotope physical property differences; specific isotope examples are not required

• Determine relative atomic masses from isotopic composition

• Interpret mass spectra for isotope identity and abundance

• Operational details of the mass spectrometer are not assessed