Bonding and Intermolecular Forces Flashcards
Covalent bonds involve the _____________ of electrons, which is usually between nonmetals and metalloids.
Sharing
Reason ionic bond forms
Cation-anion attraction
Law that dictates strength of ionic bond
Coulomb’s law
The greater the electronegativity difference between two elements sharing electrons, the more __________ the bond.
Polar
Carbon will make _______ bonds when covalently bonded.
4
4 electron domains
sp3
Tetrahedral
109°
3 electron domains
sp2
Trigonal planar
120°
2 electron domains
sp
Linear
180°
In asymmetrical molecules, bond dipoles __________ cancel, which makes the molecule __________.
Do not; polar
In symmetrical molecules, bond dipoles _________ cancel out, which makes the molecules _________.
Do; nonpolar
Carbon-to-hydrogen bonds are considered __________.
Nonpolar
CxHy polarity
Always nonpolar
A single bond contains 2 electrons, which make up ____ sigma bond(s) and ____ pi bond(s).
one; zero
A double bond contains 4 electrons, which make up ____ sigma bond(s) and ____ pi bond(s).
one; one
A triple bond contains 6 electrons, which make up ____ sigma bond(s) and ____ pi bond(s).
one; two
Lattice energy is the energy required to separate __________ in a(n) ____________ compound.
Ions; ionic
Lattice energy is larger for ionic compounds made up of _______ ions.
smaller
Lattice energy is larger for ionic compounds made up of __________ charged ions.
Larger
Formal charge formula
FC = # ve- – # electrons in lone pairs – # of bonds
When comparing two possible Lewis dot structures for a molecule, a negative formal charge should go on the _____________ electronegative element if possible.
more
The ____________ should be obeyed when drawing Lewis dot structures unless an element has a(n) ______________.
Octet rule; expanded octet
If NASL fails, use the _____ line to figure out how many electrons to distribute.
A
General ranking of IMF strength from weakest to strongest
LDF
Dipole-dipole
Hydrogen bonding
Ion-dipole
Note: LDF can be stronger for LARGE molecules due to polarizability.
LDF strength is usually weak, but can be stronger when the particle is ________________ and ______________________.
Large; spread out
Lager molecules have stronger LDFs due to _____________.
Polarizability
IMF that all particles can experience between one another
LDF
Polar molecules interacting involve what forces always?
LDF
Dipole-dipole
Note: hydrogen bonding is possible also if one molecule has a NOF bonded directly to a hydrogen atom.
Hydrogen bonding requires that the interacting molecules be _________ and one must have __________ directly bonded to a hydrogen.
Polar; N, O, or F
Boiling point and melting point _________ with stronger attractive forces.
Increase
Vapor pressure _________ with stronger attractive forces.
Decreases
Molecular solids
Held together by IMFs
Brittle
Low BP/MP
Does not conduct electricity in solid phase, liquid phase, or when in water
Ionic solids
Held together by ionic bonds
Brittle
High MP/BP
Don’t conduct electricity as solid but do conduct electricity in liquid phase or dissolved in water
Quartz (SiO2) and diamond are examples of _______________ solids.
Covalent network
Network covalent solids
Held together by covalent bonds
Hard
Very high BP/MP
Metallic solid
Held together by metallic bonds (sea of electrons w/ nondirectional bonds)
Malleable
High MP/BP
Conducts electricity in solid or liquid phase, but does not dissolve in water unless reacting with water
Molecular solids melting or boiling involve the breaking of ____________ and NOT ____________.
IMFs; bonds
IMFs should not be referred to as _________.
Bonds
Chromatography separates based on differences in ____________.
Polarity
The molecule that travels ____________ with the mobile phase is the most attracted to the mobile phase.
Fastest/furthest
Distillation separates based on ___________.
Boiling point
