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001 (part 1 of 2) 10 points
Convert a pressure of 4:25 atm to kPa. An-
swer in units of kPa.
002 (part 2 of 2) 10 points
Convert the pressure of 4:25 atm to mm Hg.
Answer in units of mmHg.
003 (part 1 of 2) 10 points
Convert a pressure of 750 torr to atmospheres.
Answer in units of atm.
004 (part 2 of 2) 10 points
Convert a pressure of 750 torr to kPa. Answer
in units of kPa.
005 (part 1 of 3) 10 points
Convert 412:159 mmHg into the unit atm.
Answer in units of atm.
006 (part 2 of 3) 10 points
Convert 3:75854 atm into the unit Pa. Answer
in units of Pa.
007 (part 3 of 3) 10 points
Convert 3:04065 kPa into the unit torr. An-
swer in units of torr.
008 (part 1 of 1) 10 points
At STP, what is the volume of 5.37 mol of
nitrogen gas? Answer in units of L.
009 (part 1 of 1) 10 points
A sample of hydrogen gas occupies 14.2 L at
STP. How many moles of the gas are present?
Answer in units of mol.
010 (part 1 of 1) 10 points
What is the volume of 71.0 g of nitrogen
dioxide gas at STP? Answer in units of L.
011 (part 1 of 3) 10 points
Suppose a 5.00 L sample of O₂ at a given tem-
perature and pressure contains 1:84 £ 1023
molecules. How many molecules would be
contained in 5.00 L H₂ at the same tempera-
ture and pressure? Answer in units of molec.
012 (part 2 of 3) 10 points
How many molecules in 5.00 L CO₂ ? Answer
in units of molec.
013 (part 3 of 3) 10 points
How many molecules in 10.00 L NH₃ ? An-
swer in units of molec.
014 (part 1 of 2) 10 points
Which contains more molecules of water,
4.00 cm3 of liquid water at 0.± C or 4.00 cm3
of water vapor (density = 4:87£10¡6 g/cm3)
at STP?
1. the liquid water
2. the water vapor
015 (part 2 of 2) 10 points
How many more molecules? Answer in units
of molec.
016 (part 1 of 1) 10 points
A balloon ¯lled with helium gas has a volume
of 453 mL at a pressure of 1 atm. The balloon
is released and reaches an altitude of 6.5 km,
where the pressure is 0.5 atm. Assuming that
the temperature has remained the same, what
volume does the gas occupy at this height?
Answer in units of mL.
017 (part 1 of 1) 10 points
Divers know that the pressure exerted by
the water increases about 100 kPa with every
10.2m of depth. This means that at 10.2m
below the surface, the pressure is 201 kPa;
at 20.4m below the surface, the pressure is
301 kPa; and so forth. If the volume of a
balloon is 2:9 L at STP and the temperature
of the water remains the same, what is the
volume 58:74 m below the water's surface?
Answer in units of L.
018 (part 1 of 3) 10 points
Use Boyle's law to ¯nd V₂ given
P₁ =428 torr, V₁ =266 mL, P₂ =717 torr.
Answer in units of mL.
019 (part 2 of 3) 10 points
Use Boyle's law to ¯nd V₁ given
P₁ = 0:8 atm, V₂ = 430:07 mL,
P₂ = 0:53 atm. Answer in units of mL.
020 (part 3 of 3) 10 points
Use Boyle's law to ¯nd P₁ given
V₁ = 3:7 £105 mL, P₂ = 139 mm Hg,
V₂ = 2:3 £103 mL. Answer in units of
mm Hg.
021 (part 1 of 2) 10 points
A helium-¯lled balloon has a volume of 2:77 L
at 30±C. The volume of the balloon decreases
to 2:33 L after it is placed outside on a cold
day. What is the outside temperature in K?
Answer in units of K.
022 (part 2 of 2) 10 points
What is the outside temperature in ±C? An-
swer in units of ±C.
023 (part 1 of 1) 10 points
A balloon ¯lled with oxygen gas occupies a
volume of 4:3 L at 34 ±C. What volume will
the gas occupy at 143 ±C? Answer in units of
L.
024 (part 1 of 3) 10 points
Use Charles's law to ¯nd V₂ given
V₁ = 65 mL, T₁ = 27 ±C, T₂ = 67 ±C.
Answer in units of mL.
025 (part 2 of 3) 10 points
Use Charles's law to ¯nd T₁ given
V₁ = 149 L, V₂ = 84 L, T₂ = 129 ±C.
Answer in units of ±C.
026 (part 3 of 3) 10 points
Use Charles's law to ¯nd V₁ given
T₁ = ¡28 ±C, V₂ = 48 mL, T₂ = 168 ±C.
Answer in units of mL.
027 (part 1 of 1) 10 points
An aerosol can contains gases under a pressure
of 4:5 atm at 27±C. If the can is left on a
hot sandy beach, the pressure of the gases
increases to 4:68 atm. What is the Celsius
temperature on the beach? Answer in units
of ±C.
028 (part 1 of 1) 10 points
The volume of a gas at 21±C and 0:31 atm is
80 mL. What volume will the same gas sample
occupy at standard conditions? Answer in
units of mL.
029 (part 1 of 1) 10 points
A meteorological balloon contains 239 L of
He at 25±C and 0:93 atm. If the volume of
the balloon can vary according to external
conditions, what volume would it occupy at
an altitude at which the temperature is ¡60±C
and the pressure is 758 atm? Answer in units
of L.
030 (part 1 of 1) 20 points
The normal respiratory rate for a human be-
ing is 15.0 breaths per minute. The average
volume of air for each breath is 505 cm3 at
20±C and 9:95 £ 104 Pa. What is the volume
of air at STP that an individual breathes in
one day? Give your answers in cubic meters.
1. 100m3=day
2. 9:98m3=day
3. None of these
4. 505m3=day
5. 505 cm3=day
6. 9:95 cm3=day
031 (part 1 of 1) 10 points
What is the volume of 0.170 g of C₂H₂F₄
vapor at 0.800 atm and 8.60±C? Answer in
units of L.
032 (part 1 of 1) 10 points
How many liters are occupied by 1.04 mol of
nitrogen at 117±C and 0.800 atm pressure?
Answer in units of L.
033 (part 1 of 1) 10 points
A tank of hydrogen gas has a volume of 24.3
L and holds 18.0 mol of the gas at 8.0±C.
What is the reading on the pressure gauge in
atmospheres? Answer in units of atm.
034 (part 1 of 1) 10 points
What is the mass of oxygen gas in a 17.8 L
container at 8.00±C and 5.00 atm? Answer in
units of g.
035 (part 1 of 1) 10 points
A chemist determines the mass of a sample
of gas to be 1.05 g. Its volume is 476 mL
at a temperature of 41.0±C and a pressure of
1.34 atm. What is the molar mass of the gas?
Answer in units of g=mol.
036 (part 1 of 3) 10 points
Calculate the volume occupied by
a) 2.28 mol of H₂ at 309 K and 1.33 atm.
Answer in units of L.
037 (part 2 of 3) 10 points
b) 0.427 mol of NH₃ at 7.40±C and 1.15 atm.
Answer in units of L.
038 (part 3 of 3) 10 points
c) 0.560 g of O₂ at 55.3±C and 0.889 atm.
Answer in units of L.
039 (part 1 of 3) 10 points
Find the molar mass of each gas measured at
the speci¯ed conditions.
a) 4.80 g of gas occupying 2.08 L at 251 K
and 1.34 atm. Answer in units of g=mol.
040 (part 2 of 3) 10 points
b) 1.90 g of gas occupying 2.96 L at 2.00±C
and 0.800 atm. Answer in units of g=mol.
041 (part 3 of 3) 10 points
c) 1.98 g occupying 361 mL at ¡31:0±C and
2.00 atm. Answer in units of g=mol.
042 (part 1 of 1) 10 points
How much H₂ gas at STP can be produced by
the reaction
2 Na(s) + 2H₂O(`) ¡! H<sub>2</sub>(g) + 2NaOH(aq)
of 3.30 g of Na and excess water? Answer in
units of L.
043 (part 1 of 1) 10 points
Nitric acid can be produced by the reaction of
gaseous nitrogen dioxide with water.
3NO<sub>2</sub>(g) + H<sub>2</sub>O(`) ¡!
2HNO₃(`) + NO(g)
If 711 L of NO₂ gas react with water, what
volume of NO gas will be produced? As-
sume the gases are measured under the same
conditions. Answer in units of L.
044 (part 1 of 3) 10 points
Methanol (CH₃OH) is made by causing car-
bon monoxide and hydrogen gases to react
at high temperature and pressure. 465 mL
of CO and 835 mL of H₂ are mixed. Which
reactant is present in excess?
1. H₂
2. CO
045 (part 2 of 3) 10 points
How much of that reactant remains after the
reaction? Answer in units of mL.
046 (part 3 of 3) 10 points
What volume of CH₃OH is produced, assum-
ing the same pressure? Answer in units of
mL.
047 (part 1 of 1) 10 points
A sample of gas is collected over water at a
temperature of 35.0±C when the barometric
pressure reading is 684 torr. What is the
partial pressure of the dry gas, given PH₂O =
42:2 torr? Answer in units of torr.
048 (part 1 of 1) 10 points
A mixture of three gases, A, B, and C, is
at a total pressure of 7:56 atm. The partial
pressure of gas A is 1:71 atm; that of gas B is
3:66 atm. What is the partial pressure of gas
C? Answer in units of atm.
049 (part 1 of 1) 10 points
If a molecule of neon gas travels at an average
of 369 m/s at a given temperature, estimate
the average speed of a molecule of butane gas
(C₄H₁₀) at the same temperature. Answer in
units of m=s.
050 (part 1 of 1) 10 points
Nitrogen e®used through a pinhole 1.7 times
as fast as another gaseous element at the same
conditions. Estimate the other element's mo-
lar mass. Answer in units of g=mol.
051 (part 1 of 1) 10 points
Determine the molecular mass ratio of two
gases whose rates of di®usion have a ratio of
14.0 : 1.
052 (part 1 of 1) 10 points
A sample of helium e®uses through a porous
container 7.10 times faster than does un-
known gas X. What is the molar mass of
the unknown gas? Answer in units of g=mol.