CHEM 1A Lecture Notes - Lecture 17: Magnetic Quantum Number, Sfermion, Effective Nuclear Charge
Document Summary
Similar properties of elements is due to valence-shell electron configurations: group # indicates # of valence-shell electrons present. New period occupation of a shell with a higher principal quantum # (n) *drops when outer electrons occupy a new shell: atomic radius: half the distance b/w the centers of neighboring atoms. Ionic radius: share of the distance between neighboring ions in an ionic solid: sum of the two ionic radii, decreasing a. r. across periods: effective nuclear charge increases. Isoelectronic: atoms and ions with the same number of electrons. Nucleus has a tighter hold on its electrons: lower principal quantum numbers, closer to nucleus, metals will readily lose their electrons, low ionization form cations readily conduct electricity. I1 decreases down a group: outermost electron is shielded from the nucleus easier to remove. Electron affinity: electron affinity (eea): energy released when an electron is added to a gas-phase atom, +: energy is released when electron attaches.
