Chemistry Ch. 4-6

Front 1

Covalent bonds __________ electrons.

Back 1

Share

Front 2

Bond Lengths can vary from ____ to ____ Angstroms.

Back 2

1.0 to 2.7

Front 3

As the difference in EN increases, bond polarity...

Back 3

increases

Front 4

Naming covalent compounds involves...

Back 4

Greek + Less EN + Greek + More EN-ide

Front 5

The 5 Lewis Postulates are...

Which ones are false?

Back 5

1. To have a stable bond, all electrons must be paired

2. All electrons are localized

3. All atoms want to be noble gases (octet)

4. All Formal Charges (FC) want to be as close to 0 as possible

5. If the FC isn't zero, then adjacent (?)

1, 2, 3

Front 6

Octet Rule

Back 6

nonmetals tend to get 8 electrons via bonding

Front 7

Formal Charge =

Back 7

electrons it came with - electrons in bond

Front 8

Ionic Charge (winner takes all) =

Back 8

electrons on its own - electrons it has in "winner takes all"

*note that the "winner" is the higher EN particle

Front 9

Bond Order (BO)

Back 9

# of shared pairs between two atoms

Front 10

If BO goes up, the bond...

Back 10

shortens

Front 11

For Lewis structures, the first element is typically put ________ of the diagram

Back 11

in the center

Front 12

Resonance Structures

Back 12

Lewis structures that differ only in the placement of the electron pairs

Front 13

In case of expanded octets...

Back 13

make the formal charge on the central atom = 0

Front 14

VSEPR

Back 14

Valence Shell Electron Pair Repulsion

Front 15

Linear bond angle =

Back 15

180

Front 16

Trigonal Planar angle =

Back 16

120

Front 17

Tetrahedral angle =

Back 17

109

Front 18

Trigonal Pyramidal angle =

Back 18

107

Front 19

Sigma Bond

Back 19

head-on overlap

Front 20

Pi Bond

Back 20

half-overlap, can only happen with p orbitals

Front 21

1 Bond =

2 Bonds =

3 Bonds =

Back 21

sigma bond

1 sigma bond, 1 pi bond

1 sigma bond, 2 pi bonds

Front 22

Sigma bonds are ___________ than pi bonds

Back 22

stronger

Front 23

Two Important Observations about the Molecular Orbital (MO) theory

Back 23

1. # of atomic orbitals = # of molecular orbitals

2. Bonding orbitals are lower in energy than their anti-bonding counterparts

Front 24

HOMO (what it stands for)

Back 24

Highest Occupied Molecular Orbital

Front 25

LUMO (what it stands for)

Back 25

Lowest Unoccupied Molecular Orbital