Chapter 6: the gaseous state Flashcards
gases have similar .., which allows us to develop models to predict their …
physical behaviors; properties
a gas is a fluid with no definite … or fixed …
shape; volume
a gas fills the
total volume of its container
because a gas is mostly empty space, a gas is
compressible
the volume of a gas … when an external force is applied
decreases
a liquid is a fluid with a
fixed volume but no definite shape
a liquid takes the …., but it does not…
shape of its container; expand to fill the container
a solid has both fixed … and …
shape; volume
liquids and solids are …
condensed phases
condensed phases: phases that are resistant to … because the spaces between the particles are … and cannot ….
volume changes; small; readily change
because the individual particles in both the liquid and solid phases are …., but in the gas phase are …, the density of the gas phase is much … than the density of either of the condensed phases
closely packed; separated; lower
density is generally expressed in .. for a gas, but the densities of liquids and solids are expressed in …
grams per liter; grams per milliliter
when a gas under atmospheric conditions condenses to a solid or a liquid, the density increases by a fact of about
1000
liquids and solids are resistant to volume changes because the spaces between the particles are
small and cannot readily change
pressure is defined as the
force exerted on a surface divided by the area of the surface
the atmosphere exerts a pressure because of the
weight of the gas molecules in the air
a barometer measures the
pressure of the amosphere
gravitational attraction pulls down the column of mercury, leaving a … above it in the tube. the column stops falling when the pressure caused by the weight of the mercury is
vacuum; equal to the pressure exerted by the atmosphere
mercury level in barometer rises→
high pressure
mercury level in barometer lowers→
low pressure
mercury is used in barometers because it is a liquid with a
high density
a manometer measures pressure
differences
(manometer) the atmosphere exerts a … on the mercury surface at the open end of the tube, and the gas within the container exerts pressure on the …
pressure; other surface of the mercury
(manometer) the difference between the heights of the 2 mercury surfaces corresponds to the difference between the
gas pressure in the container and the atmospheric pressure
for a closed-end manometer the pressure of the gas is … to the difference between the heights of the …
equal; two mercury surfaces
si unit for pressure
pascal
1 pa = 1 N/ m^2 =
1 kg/ m * s^2
1 bar =
10^5 Pa
1 atm= … mm Hg
760
1 torr = … Pa
133.3
1 atm= … torr
760
1 atm= … psi
14.7
psi is
pounds per square inch
1 atm= … kPa
101.325
1 atm= … bar
1.01325
1 atm= …. in Hg
29.92
the physical properties of all gases behave in the …, regardless of the …
same general manner; identity of the gas
4 independent properties that define the physical state of a gas:
pressure; volume; temperature; number of moles
gas laws express the relationships between the
4 independent properties of gases
volume of a gas increases as pressure
decreases
boyle’s law states that at constant …, the … of a sample of gas is … proportional to the …
temperature; volume; inversely; pressure
V=
constant X 1/P
PV=
constant
P1V1=
P2V2
doubling the temperature causes the volume of the gas to
double
charles’s law states that at constant …, the … of a fixed amount of gas is … to the absolute …
pressure; volume; directly proportional; temperature
V = (charles’s law)
constant * T
at absolute zero the volume of the gas must be
zero
at absolute zero the volume of gas is zero because all gases …. before they reach this temperature
condense to liquid/solid phase
absolute zero: … degrees C; … K
-273.15; 0
V/T =
constant
V1/T1=
V2/T2
avogadro proposed that at thes ame temperature and pressure, equal volumes of gases contain the
same number of particles
avogadro;s law states that at constant pressure and temperature, the volume of a gas sample is …
proportional to the number of moles of gas present
(avogadro’s law) V=
constant * n
V1/n1 =
V2/n2
combined gas law:
P1V1/n1 = P2V2/n2
temps must be expressed in
kelvins
R with units Latm/ molK
0.08206
R with units kgm^2/s^2mol*K
8.314
R with units J/mol*K
8.314
R with units cal/mol*K
1.987