Match each description with the appropriate term. a particular variety of an element as defined by its atomic mass a component of an atomic nucleus with a mass of 1 atomic mass unit and a charge of 1" 1. atomic number the name applied to protons and 2. isotope neutrons (the parts of an atom's nucleus) 3. mass number the total number of protons and neutrons in an atom; frequently 4. neutron written after the name of an element to identify a specific 5. nucleon isotope 6. proton a component of an atomic nucleus with a mass of 1 atomic mass unit and no net charge determines the identity of an element