Vocabulary Flashcards
isotopes
atoms with different number of neutrons
ions
lost or gained electrons (positive = cations, negative = anions)
atomic number
equal to the number of protons, defines the element
atomic mass
equal to the number of protons plus the number of neutrons
beta radiation
medium radiation, an electron (^0 -1e) is ejected and a neutron becomes a proton
alpha radiation
weakest radiation, a helium nucleus ( ^4 2He ) is emitted
energy levels
ring on a Bohr model
gamma radiation
strongest radiation, a high energy photon ( ^0 0Y) is emitted
orbitals
region of space where you are most likely to find an electron
valence electrons
electrons on the outermost ring
hund’s rule
electrons spread out in an orbital type before they pair up
aufbau principle
electrons occupy lower energy levels first
pauli exclusion principle
electrons in an orbital must have opposite spins
metals
left side of PT, luster, malleable, ductile, good conductors
metalloids
along stair step line of PT, mixed properties