finals Flashcards
gases tend to have ___
low molecular weight
pressure is the same no matter the ____
element
1 atm = ___ mm Hg = ___ torr = ___ Pa = ___psi
760 mm Hg, 760 torr, 1.01325 x 10^5 Pa, 14.70 Psi
manometer measure the pressure of _____
gas
open ended manometer = ___ , closed ended =___
compare to 1 atm (760 mm Hg), compare to 0 mm Hg
boyles law
volume is inversely proportional to pressure V= 1/p
boyles law math
P1V1=P2V2
Charles law
temp is proportional to volume
Charles law math
V1/T1 = V2/T2
Combined gas law
(P1V1)/T1 = (P2T2)/T2
Gay-Lussac’s law
temp goes down, pressure goes down
Gay-Lussac’s math
P1/T1 = P2/T1
avogandros law
volume is proportional to moles at STP
ideal gas law
Volume is proportional to (moles*temp)/pressure
ideal gas law math
PV=nRT
R in ideal gas law
0.08206 (Latm)/(molK)
density version of PV=nRT
m/V=MP/RT (M=molarity)
Daltons law of partial pressures
IT DOESNT MATTER THE WEIGHT PRESSURE WILL ALWAYS BE THE SAME FOR EACH PARTICLE Ptotal = P1 + p2 + p3 + p4 +……
mole fraction for gases
P1/Pt = (N1RT/V)/(ntRT/V) = N1/Nt
mole fraction
mole of particular gas/total moles of all gas
pressure ratio = _______
= mole ratio
kinetic molecular theory (5)
- gases are in continuous motion
- The volume of the molecules is negligible relative to the total volume in which the gas is contained (FALSE)
- there are no attractive and repulsive forces (FALSE)
- energy can be transferred between molecules during collisions, but average energy does not change.
- the average kinetic energy is proportional to the absolute temperature
average kinetic energy equation
KE=1/2mv^2
lighter gases move ____ and have greater _____ of speed and heavier move ____ and haver less ____ of speed
faster, distribution, slower, distribution
learn about most probable speed, root speed and the other one
on it
u(rms) equation (average kinetic energy of gas)
square root of 3RT/M
R in average kinetic energy of gas
= 8.314 J/molK = (kgm^2/S^2)/mole*K
effusion
escape of gas molecules through a tiny hole into an evactauted space (leaky air tank)
diffusion
gas spreads throughout a space (like febreeze)
mean free path
average distance a gas travels before a collision (pressure increases, distance decreases)
rate of effusion is related to ____
collision rate
Grahams law
R1/R2= square root of Mass2/Mass1 (compares the rate that gases effuse)
deviations from ideal gas happens when _____ and ____
theres high and low pressure
at low temp, you move ____ and have to deal with _____ forces
slower, attractive
van der Waal’s equation for real gases
(P + (n^2a)/V^2)*(V - nb) = nRT