Periodic Trends and Attraction

Periodic trends and electron characteristics

coulombic attraction

force of attraction between oppositely charged particles (protons and electrons)

coulombic potential

energy associated with coulombic attraction

atomic radius

distance from the center of the nucleus of an atom to the edge of the electron cloud

ionization energy

amount of energy required to remove the most loosely held electron from an atom — in the valence level (ionizing the atom into +1); opposite of coulombic

electron affinity

the amount of energy released when an electron is gained by a neutral atom in the gaseous state to form a (-) ion

electronegativity

ability of an atom to attract shared electrons away from another atom in a bond; how strongly an atom pulls on electrons from another atom while bonded

effective nuclear charge

number of protons - number of valence electrons; larger number means a greater core charge and stronger attraction to electrons

successive ionization

ionization energy increases for each electron removed from the electron cloud; dramatic increase for the electron following the final valence electron

group 2 → group 13 ionization trend exception

(s²) → (s²p¹)
the p sublevel is higher in energy and farther from the nucleus, which is greater than the attraction from the additional proton; decreases the coulombic attraction/potential and therefore the ionization energy

group 15 → group 16 ionization trend exception

(p³ ↑ ↑ ↑) → (p⁴ ↑↓ ↑ ↑)
the paired electron spin level creates repulsion, which is greater than the attractive force from the additional proton; decreases the coulombic attraction/potential and therefore the ionization energy