CEM 141 Lecture Notes - Lecture 23: Atomic Number, Magnesium, Effective Nuclear Charge
Document Summary
Review concept: using af(cid:271)au"s prin(cid:272)iple and hund"s rule for filling ele(cid:272)tron or(cid:271)itals. Af(cid:271)au"s prin(cid:272)iple the lowest energy orbitals are occupied first by electrons. Hund"s rule singular electrons occupy each subshell before their pairs of opposite spin occupy the same subshells. Inverse relationship between atomic radius and ionization energy this is due to effective nuclear charge. Higher effective nuclear charge causes smaller atomic radius. Higher effective nuclear charge (and smaller atomic radius) also causes larger ionization energy. The ionization energy across rows of the periodic table does not rise consistently (e. g. boron, oxygen) The repulsion between electron pairs within a subshell is very slight, which makes it slightly easier to remove. This pattern of more easily removed electrons in pairs in the p orbitals can be generalized to group 16 elements. The pattern of electrons in less stable orbitals (that lowers the ie) is applicable to elements in group 13. The 1st, 2nd, and 3rd ionization energies for magnesium goes from.
