chapter 10 review Flashcards
gas
most freedom of the states
mixes freely with other gases, changes its shape and volume to fit into any container, compressible
pressure=
force / area
how do you measure atmospheric pressure
barometer
manometers
used to measure the pressure of a sample of gas
Pgas(mm Hg)=
Patm +/- height difference
1 mmHg=
1 torr
1 atm=
760 mm Hg/torr
1 atm=
101325 Pascals or 101.325 KPa
boyles law
pressure and volume have an inverse relationship
P1V1=P2V2
if volume increases (bl)
pressure decreases
if pressure increases (bl)
volume decreases
charles law
volume and temperature are directly related
v1/t1 = v2/t2
if temperature increases (cl)
volume increases
avogadros law
volume and moles of gas are directly related
v1/n1=v2/n2
if volume increases (al)
moles increase
1 mol of an ideal gas occupies
22.4 L at STP
ideal gas law
PV=nRT
ideal gas law R
0.08296 L atm/mol K
gasses follow the ideal gas law best at
low pressures and high temperatures
M (molar mass)=
mRT/PV
density (for gas)
MP/RT
the pressure gases are additive…
the total pressure of a mixture of gases is the sum of the partial pressures of each gas
p total eq (2)
sum of p1+p2+p3…
=ntotal(RT/V)
x1=
n1/ntotal=p1/ptotal
p1=
(n1/ntotal)Ptotal
kinetic molecular theory
-vol of gas is negligible
-particles are in constant motion and hit the walls of the container to create pressure
-particles of gases don’t attract or repel each other (elastic collisions)
-average kinetic energy of a gas is directly proportional to the temperature (kelvin) or a gas
(KE)avg=
3/2 RT
velocity=
squareroot(3RT/M)
urms R
8.314 JK mole
slower urms=
bigger atomic mass
faster urms=
smaller molar mass
effusion
passage of gas through tiny orifice into an evacuated chamber
rate of effusion gas1/ rate of effusion gas 2 =
√MW2/√MW1
diffusion
mixing of gases
