solids and liquids Flashcards
density
mass/volume
increased temp, ___ density
decreases
stronger forces = ___ density at same temp
higher
surface tension
force on liquid surface opposing expansion of the surface area
liquids tend to ___ surface area
minimize
surface tension ___ with increasing temp
decreases
cohesive forces
attraction of molecules to similar molecules
adhesive forces
attraction of molecule to different molecules
viscosity
measure of a liquid’s resistance to flow
viscosity ____ as temperature is increased
decreases
vapor pressure is controlled by
attractive forces, temperature, surface area
Heat of vaporization
energy required for a certain amount of substance to evaporate
boiling point
temperature at which liquid will begin to boil at atmospheric pressure
distillation
process whereby liquid is converted to vapor by boiling and condensed back to liquid by cooling
phase change
changing from one phase of matter to another
phase change determined by
-availability of energy
-forces holding molecules together
supercooling
liquid that remains in the liquid state even after being cooled below freezing point
superheating
liquid rapidly heated so it does not boil immediately
solubility
depends in relative strength of solute-solute interactions compared to solute solute or solvent solvent
ion-ion interaction
Interactive force between ions of opposite charge that results in an ionic bond
At lower temperatures gas dissolved in
water has ____ kinetic energy, and dipole-
induced dipole interactions between
solute and solvent molecules keep more
gas dissolved.
less
At higher temperatures molecules have ______ kinetic energy, which overcomes
solute–solvent interactions and reduces
solubility.
more
The solubility of a gas in a liquid depends
on the _____ ______ of the gas in the air
above the surface of the liquid.
partial pressure
The amount of gas that dissolves in a
liquid depends on the ____ and
_______ of collisions that the gas
molecules have with the surface of the
liquid.
frequency; number
The more collisions, the more gas
molecules that may form intermolecular
attractions with the _____.
solvent
Colligative Properties of Solutions
Solution properties that depend on concentration of solute particles, not the identity of particles.
Vapor Pressure
pressure of molecules above solution when equilibrium reached between evaporation and condensation
volatile
easily evaporated at normal temperatures.
when nonvolatile solute is dissolved in solvent, vapor pressure is ___
decreased
solute is nonvolatile
only solvent molecules at surface will be able to escape
raoult’s law
Vapor pressure (P) of volatile component of solution = product of mole
fraction (X) and vapor pressure of pure compound (P°) at same temp.
Only ____ ______follow Raoult’s Law quantitatively
ideal solutions
for mixtures containing more than one volatile component
Partial pressure of each volatile component contributes to total vapor
pressure of solution.
fractional distillation
Method of separating a mixture of compounds based on their different
boiling points
solutions are _____
homogeneous
suspensions are ____
heterogenous
colloidal dispersions are ____
heterogenous
