The forces holding together the nucleus are large. And so are the energies involved.
Radioactivity is a natural process. Certain nuclei fall apart and emit ionizing radiation as
Radiation and radioactivity are dangerous but useful. They can cause illness, but they
can cure or diagnose as well. Duke was here.
Remember: Particles have a wave nature
A classical particle of mass m bounces back and forth between two boundaries.
Matter waves moving in opposite directions create standing waves.
Only certain wavelengths meet the boundary conditions, so only certain energies are
1 2L h 2
E n 2m ¿ = 8mL 2 n
Confining neutrons and protons in the “box” of the nucleus means that their allowed
energies are enormous.
Number of protons determines the element, number of neutrons the isotope
Most elements have more than one stable isotope.
Z = # of protons
N = # of neutrons
Mass number A = Z + N
Atomic number: Z