unit 3 vocab Flashcards
pressure
the amount of force per unit area. F/A
barometer
an evacuated glass tube, the tip of which is submerged in a pool of mercury. used to measure pressure
torr
a millimeter of mercury (Hg)
manometer
u-shaped tube containing a dense liquid, usually mercury. used to measure the pressure of a sample relative to atmospheric pressure
boyle’s law
volume is proportional to 1 divided by pressure
charles’ law
volume is proportional to temperature
avogadro’s law
volume is proportional to number of moles
ideal gas law
PV=nRT
ideal gas
hypothetical gas that exactly follows the ideal gas law
molar volume of an ideal gas at STP
22.4 L
STP
standard temperature and pressure
partial pressure
the pressure due to any individual component in a gas mixture (Pn)
mole fraction
the number of moles of a component in a mixture divided by the total number of moles in the mixture
vapor pressure
the partial pressure of water vapor in a gas from the gas collection process after a chemical reaction
dalton’s law
the total pressure of a gas mixture is the sum of the partial pressures of its components
kinetic molecular theory
- particles are negligibly small in volume but have mass
- the average kinetic energy of a particle is proportional to the temperature in kelvins, atom’s motion is due to thermal energy
kinetic molecular theory
- particles are negligibly small in volume but have mass
- the average kinetic energy of a particle is proportional to the temperature in kelvins, atom’s motion is due to thermal energy
- when particles collide, there’s no loss of energy
mean free path
the average distance that a molecule travels in between collisions. increases as pressure decreases
diffusion
the process by which gas molecules spread out in response to a concentration gradient. influenced by the root mean square velocity
effusion
the process by which a gas escapes from a container into a vacuum through a small hole
graham’s law of effusion
rate A/rate B = square root of MB/MA
amorphous
a solid in which the atoms don’t have an sort of long-range order
miscibility
a liquid’s ability to mix without separating into two states
surface tension
the energy required to increase the surface area of a liquid by a unit amount. decreases as intermolecular forces decrease
viscosity
a measure of the resistance of a liquid to flow. increases with molar mass
poise (P)
unit used to measure viscosity, 1g/cm*s
capillary action
the ability of a liquid to flow against gravity up a narrow tube due to adhesive and cohesive forces
cohesive forces
attraction between molecules in a liquid. wants to hold together