Intermolecular forces Flashcards
what do inter particle forces affect
melting pt, boiling pt, heat of vaporization, heat of fusion, viscosity, and vapor pressure
vapor pressure
number of evaporated particles (higher VP=more particles)
ionic intermolecular forces
strong forces, solids at room temp, lattice energy used to compare melting points
covalent intermolecular forces
IMF
3 types of IMF
1) dipole dipole- occurs between polar molecules
2) hydrogen bond (h bond)- stronger than d/d, but a variation of it. occurs when H bonds to NOF
3) London dispersion forces (LDF)- occurs in all substances. More electrons (more polarizable) the higher the LDF.
As molar mass increases what happens to LDF
it increases (more electrons)
Solute
the thing that gets dissolved
solvent
the thing doing the dissolving (H20 in IMF problems)
What does a stronger IMF between solute and solvent do to solubility
it makes it more soluble
what makes a solute unable to dissolve
if it has no dipole dipole or H bond, only LDF (non-polar)
order the three IMFs from least to most soluble
d/d, h bond, LDF
Absorbence equation
A= molar absorptivity (path length) (molarity)
Chromotography
used to seperate liquid solutions.
what is the mobile phase in chromotography
solvent. (attraction due to polarity difference). When solvent is non polar, stationary phase is polar.
distillation
uses vapor pressure to separate solutions. Lower Vapor pressure= higher boiling point/greater IMF.
