atomic structure and properties

atomic radii

outer electrons are closer to nucleus (higher binding energy) —> SMALLER

outer electrons are further from nucleus (lesser strength of attraction) —> BIGGER

PES peaks —> core/valence electrons

peaks with lowest binding energy (furthest from Y axis) —> VALENCE ELECTRONS

height of peaks = # of electrons → same height = same # electrons in that level

first ionization energy

energy required to remove LEAST BOUND (outermost) electron from NEUTRAL atom of element —> lower binding energy = lower ionization energy (thus, furthest from Y axis = valence electrons)

height of peaks

corresponds to signal intensity (AKA # OF ELECTRONS IN SUBSHELL)

electron affinity

definition: amount of energy released when electron is ADDED to an atom (negative = energy GAINED —> does not want electron = FAVORABLE)

generally becomes more favorable (more negative) as you go ACROSS THE PERIOD

— increase in effective nuclear charge = more favorable (NEGATIVE) electron affinity

predicting PES of another element

peaks shift TOWARDS Y AXIS (binding energy increasing) if more protons —> GREATER NUCLEAR CHARGE (greater pull on electrons)

peaks shift AWAY FROM Y AXIS (binding energy decreasing) if smaller nuclear charge (LESS PROTONS)