atom
the smallest component of an element having the chemical properties of the element
atomic mass
the weighted average of the masses of the isotopes of an element
atomic number
the number of protons in the nucleus of an atom
electron
negatively charged particle
excited state
A state in which an atom has more energy than it does at its ground state
ground state
the lowest energy state of an atom
isotope
atoms of the same element that have different numbers of neutrons
mass number
the sum of the number of neutrons and protons in an atomic nucleus
neutron
a subatomic particle that has the same mass as a proton but no electric charge
nucleus
the positively charged dense center of an atom
orbital
a region in an atom where there is a high probability of finding electrons
proton
positively charged particle