Number of Syllables
1. Tell a student why valence is a useful concept, but that molecular orbital theory is somtimes necessary to explain reality.
keep track of numbers of bonds
predict reactivity of elements in a group
non-bonding and anti-bonding orbitals
2. Show a student how the valency of each element in the second row of the periodic table is determined.
number of electrons in the 2-shell
share pairs of electrons
boron, carbon, nitrogen, oxygen, fluorine