Bonding Flashcards
What is the octet rule?
Losing or gaining electrons to achieve noble gas configuration.
C, N, O, F, Na, Mg always abide by the octet rule!
What is the formation of an ionic bond between?
(transfer of electrons)
Metal and nonmetal
Example: NaCl
What is the formation of a covalent bond between?
(sharing of electrons)
2 nonmetals
Example: CO2 (similar electronegativities)
What kind of sharing of electrons occur in a nonpolar covalent bond? Polar covalent bond?
Nonpolar covalent bond: equal sharing of electrons
Polar covalent bond: unequal sharing of electrons
[Mnemonic]
NEPA or NEPUN
(how to remember the sharing of electrons in nonpolar or polar covalent bonds)
NEPA or N E P U N
Nonpolar = equal sharing
Polar = unequal sharing
What kind of bond forms between a Lewis acid and Lewis base?
Coordinate covalent bond
(a lone pair of one atom attacks another atom with an unhybridized p-orbital to form a bond)
What are the four characteristics of ionic compounds?
- high melting and boiling points
- good conductors of heat and electricity
- soluble in water
- form crystal lattices (in solid state)
Rank these bonds from longest to shortest:
C─C, C=C, C≡C
- longest C─C
- medium C=C
- shortest C≡C
Bond strength is inversely related to bond length.
What is bond energy?
Energy required to break a bond.
Single bond < Double bond < Triple bond
(Triple bonds have the greatest bond energy because more energy is required to break their bonds, in comparison to a single bond.)
Bond energy = bond strength
Bond energy = bond strength
Example: Triple bonds have the greatest bond energy and strength.
Sigma (σ) and pi (π) bonds are made from the overlap of two orbitals. Which kind of bonds does a single bond contain? Double bond? Triple bond?
Single bond: sigma
Double bond: 1 sigma and 1 pi
Triple bond: 1 sigma and 2 pi
In a polar covalent bond, where are the positive and negative ends of a dipole?
Positive end: at the less electronegative atom
Negative end: at the more electronegative atom
[Mnemonic]
Have No Fear Of Ice Cold Beer
(how to remember the seven diatomic elements)
They also form a seven on the periodic table with the exception of H.
Have No Fear Of Ice Cold Beer
H2
N2
F2
O2
I2
C2
Br2
How to calculate formal charge:
[Should - has]
For resonance structures, which structure is the most stable?
The one with the negative formal charge on the most electronegative atom.
What are some exceptions to the octet rule?
Incomplete octet: H, He and Li (are all stable with 2 electrons), Be (4) and B (6)
Expanded octet: Period 3 and greater (stable with 8+ electrons)
Odd numbers of electrons: Example: NO which has 11 e-
What is the difference between electronic geometry and molecular geometry?
Electronic geometry: Count bonds and lone pairs
Molecular geometry: Count bonds
Example: CH4, NH3, and H2O all have tetrahedral electronic geometry, but differ in their molecular geometry. CH4 is tetrahedral, NH3 is pyramidal, and H2O is bent/angular.
What is the molecular geometry for water?
Bent (or angular)
What are the three kinds of intermolecular forces?
- hydrogen bonding
- dipole-dipole interactions (+ end of one molecule is attracted to the - end of another molecule and vice-versa)
- London dispersion forces (VDW)
Dipole–dipole interactions are present in the solid and liquid phases but become negligible in the gas phase because of the significantly increased distance between gas particles.
Which intermolecular force is the weakest?
London dispersion forces
(Causes temporary induced dipoles in a molecule and other molecules nearby which change and shift moment to moment. )
Which intermolecular force is the strongest?
Hydrogen bonding
Hydrogen bonding occurs when hydrogen is bound to which three atoms?
- F
- O
- N
