2.2 Intramolecular force and Potential Energy

Covalent bonds are the bonds between ______ when they ______

two nonmetals; share valence electrons.

Different types of covalent bonds:

Polar or nonpolar

In polar covalent bonds, electrons are shared equally/unequally

unequally

In nonpolar covalent bonds, electrons are shared equally/unequally

equally

Covalent bonds can what three types of bonds?

single, double, triple bonds

What type of bond do covalent bonds have if there are resonance structures?

Average of single, double, triple bonds

Covalent bonds occur at the highest/lowest energy state.

lowest

The low energy state of covalent bonds happens when:

the attraction between the nuclei is greatest for the shared electrons, but the repulsions between electrons and between the nuclei is the least.

What happens when atoms in covalent bonds are too close together?

The nuclei will repel each other

What happens when atoms in covalent bonds are too far apart?

the attraction will not be enough to hold them together

Bond energy is the energy required when:

breaking a bond

the energy released when a bond is formed

bond energy

Compare the magnitude and sign of energy required when breaking a bond vs energy released when forming a bond:

Same magnitude but different sign

Larger atomic radii increase/decreases the bond length.

increases

Longer bond length increases/decreases the bond energy

decreases

Increasing the bond order increases/decreases the bond energy

increases

Why does increasing the bond order increase the bond energy?

there are more electrons involved and therefore greater coulombic attraction and the bond length has decreased.

The energy to separate ions in ionic compounds is their:

lattice energy

The change in energy that takes place when gaseous ions are combined to form an ionic solid.

Lattice energy

Combining ions will absorb/release energy.

release

Lattice energy can be represented using:

a modification of Coulomb’s law where the energy is proportional to the charges and inversely proportional to the distances between the nuclei.

Why is energy proportional to the charges in terms of lattice energy?

Larger charges = more attraction = more energy required to separate the ions

Why is energy inversely proportional to distance between the nuclei in terms of lattice energy?

Smaller radii = more attraction = more energy required to separate the ions