unit 7 - liquids, solids, and solutions Flashcards
cohesion
the attraction of molecules in a liquid to EACH OTHER due to intermolecular forces
adhesion
attraction of molecules in a liquid TO CONTAINER causing it to cling to the sides
concave meniscus
- adhesive forces are stronger than cohesive forces
- molecules in liquid are more attracted to the container than to each other
- example: water and glass tube
⌣
convex meniscus
- cohesive forces are stronger than adhesive forces
- molecules in liquid are more attracted to each other than to the container
- example: mercury and glass tube
⌢
surface tension definition & surface tension in water
definition: resistance to an increase in its surface area (polar molecules)
in water: water’s cohesive properties which result from hydrogen bonding and polarity require a lot of energy to break, creating high surface tension
relationships b/w boiling points and IMF’s
and vapor pressure and boiling point
- stronger the intermolecular forces, higher the boiling points (direct relationship)
- greater the vapor pressure, lower the boiling point (indirect relationship)
vapor pressure (formal definition and 3 factors that influence it)
pressure caused by the evaporation of liquids
influenced by surface area, IMFs, and temperature
- surface area: substances with large molar masses have low vapor pressures
- IMF: stronger the IMF, lower the vapor pressure
- temperature: as temp increases, so does vapor pressure
vaporization vs evaporation
vaporization: change from liquid to gas AT boiling point (phase change- liquid to gas)
evaporation: changing from liquid to gas BELOW boiling point (conversion of liquid to its vapor)
super cooling
liquid keeps cooling down even below freezing
(if given a graph and water keeps going down even after 0 degrees and 1 atm pressure, it is being supercooled)
boiling point vs normal boiling point
boiling point: point at which vapor pressure equals the atmospheric pressure (can be anything) (depends on altitude- water boils faster on a mountaintop)
normal boiling point: temperature at which the vapor pressure of the liquid is 1 atm (specific value)
why is liquid the most dense phase of water?
even if you apply the max pressure, the particles stay liquid
(creates open lattice structure when becomes solid)
what happens after the critical point? and where is the critical point? and what is the critical point temp and pressure for water?
after critical point, molecule will exist as a gas, cannot be converted to liquid at any time
critical point is that last point of the graph where the line trails off..
water: temp is 374 C and 218 atm
sublimation, deposition, condensation
sublimation: solid to gas
deposition: gas to solid
condensation: gas to liquid
molarity formula (M)
moles of solute / liters of solution
mass percent formula (%)
(mass of solute / mass of solution) x 100
