10.5, 10.7 Covalent Bonding: Lewis Structures

10.5 Covalent Bonding: Lewis Structures, 10.7 Lewis Structures of Molecular Compounds and Polyatomic Ions

bonding pair

a pair of electrons shared between two atoms, often represented by a dash to emphasize that it constitutes a chemical bond

lone pair

aka nonbonding electrons, a pair of electrons associated with only one atom

nonbonding electrons

aka lone pair electrons, electrons in a Lewis structure that are not in a chemical bond

double bond

the bond that forms when two electron pairs are shared between two atoms

triple bond

the bond that forms when 3 electron pairs are shared between 2 atoms

triple, double, single

In general, _______ (single/double/triple) bonds are shorter and stronger than _______ (single/double/triple) bonds which are shorter and stronger than _______ (single/double/triple) bonds.

halogens

Hydrogen and the _________ (alkali metals/alkaline earth metals/halogens/noble gases) are all diatomic molecular elements, as predicted by Lewis theory.

oxygen

_______ generally forms either two single bonds or a double bond in its molecular compounds, as predicted by Lewis theory.

nondirectional, directional

Ionic bonds are ___________ (directional/nondirectional) while covalent bonds are highly ___________ (directional/nondirectional).

individual molecules

The Lewis model predicts covalently bonded compounds will be found as __________________ (array like ionic compounds/individual molecules).

low

The Lewis model predicts that molecular compounds have ___ (high/low) melting and boiling points at generally less than 300 degrees celsius. When a molecular compound melts or boils, the molecules themselves remain intact, only the relatively weak interactions between molecules must be overcome.

true

(true/false) Molecular compounds are found in all three states at room temperature.

intermolecular

The Lewis model predicts that the hardness and brittleness of molecular compounds should vary depending on the strength of _____ (intramolecular/intermolecular) attractive forces.

charged

The Lewis model predicts that neither molecular solids nor liquids should conduct electricity as there are no _______ particles to allow the material to conduct (oversimplification).

terminal

Hydrogen atoms are always _________; they have only a single valence electron to share and require only a duet, so they can form just one bond.

more, less

When writing the skeletal structure of a Lewis structure, place the _____ (more/less) electronegative elements in terminal positions and the ____ (more/less) electronegative elements (other than hydrogen) in the central position).