CRAM: Intermolecular Forces Flashcards
(31 cards)
Intermolecular Forces (IMFs)
Forces that attract or repel entire molecules, arising from differences in charge between them.
Intramolecular Forces
Forces that hold atoms together within a molecule.
London Dispersion Forces (LDFs)
The weakest type of intermolecular force present in all molecular substances, including nonpolar molecules.
Dipole-Dipole Forces
Attractions between polar molecules due to permanent dipoles.
Hydrogen Bonding
A strong dipole-dipole attraction that occurs between molecules containing hydrogen bonded to fluorine, oxygen, or nitrogen.
Ion-Dipole Forces
Attractive forces between ions and polar molecules.
Coulomb’s Law
The principle stating that the closer two particles are, the stronger the attraction.
Polarizability
The ease with which the electron cloud of a molecule can be distorted.
Temporary Dipoles
Short-lived distributions of electron density in molecules that create partial charges.
Permanent Dipoles
A consistent separation of charge within polar molecules.
Electrostatic Attraction
The attraction between positively and negatively charged regions of molecules.
Factors Affecting LDF Strength
Molecular size and shape influence the strength of London Dispersion Forces.
Impact of IMFs on Boiling Point
Stronger intermolecular forces lead to higher boiling points.
Strength Order of IMFs
Ion-Dipole > Hydrogen Bonding > Dipole-Dipole > London Dispersion Forces.
Hydrogen Bond Effects on Water
Responsible for water’s high specific heat, cohesion, adhesion, and solubility.
Ion-Ion Attractions
Electrostatic attractions that occur between oppositely charged ions within an ionic compound.
Molecular Shape Impact
The orientation of dipoles in molecules can affect the strength of dipole-dipole interactions.
Ion-Dipole Behavior in Solutions
Ion-dipole forces contribute to the solubility of ionic compounds in polar solvents.
LDF Presence in Molecules
Present in all molecules and always alongside other types of IMFs.
High Polarity Effect
More polar molecules produce stronger dipole-dipole forces.
Boiling Point and IMFs
The boiling point of a substance increases with the strength of its intermolecular forces.
Hydrogen Bond Characteristics
Occurs between elements F, O, and N bonded to hydrogen.
Surface Tension and IMFs
Stronger intermolecular forces lead to higher surface tension in liquids.
Viscosity and IMFs
Higher viscosity is correlated with stronger intermolecular forces.
