radioactivity - tendency to decay, emit particles
- radionuclides - radioactive nuclei
- radioisotopes - atoms w/ radioactive nuclei
- alpha radiation - emitting alpha particles (helium-4 nuclei)
- atomic number decreases by 2
- atomic mass decreases by 4
- beta radiation - emits electrons from unstable nucleus
- neutron >> proton
- atomic number increases by 1
- atomic mass stays the same
- gamma radiation - emits high-energy photons
- accompanies other radioactive emissions
- doesn’t change atomic number/mass
- electron capture - nucleus gains electron from surrounding electron cloud
- proton >> neutron
- atomic number decreases by 1
- atomic mass stays the same
nuclear stability - depends on multiple factors
- neutron-proton ratio - neutron # > proton # to ensure stability in atoms w/ large atomic numbers
- belt of stability - area in which all stable nuclei are found
- all nuclei w/ 84+ protons are radioactive
- nuclei above belt of stability use beta emission >> increases proton #, decreases neutron #
- nuclei below belt of stability use electron capture, positron emission >> decrease proton #, increase neutron #
- nuclei with over 84 protons use alpha emission
- radioactive series - aka nuclear disintegration series
- 3 naturally occurring series end with lead
- stability not achieved w/ a single emission (needs a series of emissions)
- magic numbers - 2, 8, 20, 28, 50, 82 protons; 2, 8, 20, 28, 50, 82, 126 neutrons
- usually more stable when w/ these numbers
Subject:
Subject X2:
