Temperature & Pressure Conversions

I.  Convert the following units of pressure:
1.)    2.00 atm to mm Hg
2.)    115 kPa to atm
3.)
500. mm Hg to atm
4.)    3.5 x 104 torr to mm Hg
5.)
1800. mm Hg to kPa
6.)    93,500 Pa to atm
7.)
950. torr to atm
8.)    0.490 atm to kPa
II.
1.)    35 oC to Kelvin
2.)    120 oC to Kelvin
3.)
-25 oC to Kelvin
4.)
-227 oC to Kelvin
5.)
standard temperature in Kelvin and Celsius
6.)    298 K to oC
7.)
100. K to oC
8.)
5 Kelvin to oC

Ideal Gas Equation 1
1.)
What is the pressure exerted by 2.0 moles of an ideal gas when it occupies a volume of 12.0 L at

2.)  A flashbulb of volume 2.6 cm3 contains O2 gas at a pressure of 2.3 atm and a temperature of 26oC.
How many moles of O2 does the flashbulb contain?                  (Answer:  2.4 x 10-4 moles)

3.)  If 0.20 moles of helium occupies a volume of 64.0 liters at a pressure of 0.15 atm, what is the
temperature of the gas?                                                                                (Answer:  580 K)

4.)  What is the volume of 0.35 moles of gas at 1.7 atm of pressure and a temperature of 100 K?

5.)  What is the pressure of 1.5 moles of an ideal gas at a temperature of 150 K and occupies a volume
of 20.0 liters?                                                                                              (Answer:  0.92 atm)

6.)  How many moles of gas occupy 16.2 liters at a pressure of 1.05 atm and a temperature of 37oC?

Ideal Gas Equation 2
1.
Calculate the volume of exactly 1.00 mole of a gas at STP.                                                      (22.4 L)

2.    How many moles of nitrogen are present in 17.8 liters at 27 oC and 1.3 atm pressure?   (0.94 moles)

3.    What is the pressure of 2.3 moles of carbon dioxide at 235 K occupying 23.7 liters of space?      (1.9 atm)

4.    If there are 4.02 x 1023 molecules of N2O in a sample, how many moles are there?                    (0.668 moles)

5.    Using your answer from # 6, calculate the pressure of the gas if it occupies 27,025 cm3 of space
at 38.0 oC.                                                                                                                          (0.631 atm)

6.    How many grams of ammonia gas (NH3) are present in 35.0 dm3 of space at 78.3 K and 0.853 atm
of pressure?                                                                                                                       (78.9 g)

7.    What is the temperature of 34.2 grams of sulfur dioxide occupying 30.0 liters of space and having
a pressure of 800. torr?                                                                                                       (720. K)

8.  What is the pressure (in mm Hg) of 79.4 grams of boron trifluoride with a volume of 20.0 L and
a temperature of 245 K?                                                                                                       (889 mm Hg)

9.  How many grams are in a sample of arsenic trifluoride that has a volume of 17,600 mL and a
temperature of 92 oC and a pressure of 108,732 Pa?                                                  (83 g)

10.  How many kilopascals of pressure are exerted by 23.8 liters of oxygen with a mass of 175 grams
at a temperature of 58 oC?                                                                                                   (632 kPa)

11.    How many moles of argon are in 30.6 liters at 28 K and 658 mm Hg of pressure?                    (12 moles)

12.    How many grams of argon are found in # 11?                                                                      (480 g)

Applications of Ideal Gas Equation
1.)
What pressure is exerted by 1.0 mole of an ideal gas contained in a 1.0 L vessel at 0.0 oC?

2.)  What is the density of a sample of ammonia gas, NH3, if the pressure is 0.928 atm and the
temperature is 63.0 oC?                                                                                (Answer:  0.572 g/L)

3.)  Calculate the molar mass of a gas if 4.5 L of the gas at 785 torr and 23.5 oC has a mass of 13.5

4.)  0.453 moles of a gas confined to a 15.0 L container exerts a pressure of 1.24 atm on the walls of
the container.  What is the temperature of the gas (in oC)?                               (Answer:  227 oC)

5.)  5.4 grams of carbon dioxide are confined to a 20.0 L container at a temperature of 32.5 oC.  What
pressure does the gas exert?                                                                         (Answer:  0.15 atm)

6.)  2.125 grams of a gas in a 1.25 L container exert a pressure of 0.838 atm at 40.0 oC.  What is the
molar mass of the gas?                                                                                 (Answer:  52.1 g/mole)

7.)  To what temperature must 10.0 grams of ammonia gas (NH3) have to be heated in a 15.0 L
container in order for it to exert a pressure of 3.50 atm?                                  (Answer:  1090 K)

8.)  2.0 x 10-5 grams of hydrogen gas at 155 oC exert a pressure of 322.5 torr on the walls of a small
cylindrical tube.  What is the volume of the tube?                                            (Answer:  8.3 x 10-4 L)

Gas Law Problems
1.)
The gas pressure in an aerosol can is 1.5 atm at 25 oC.  Assuming that the gas inside obeys the
ideal gas equation, what would the pressure be if the can were heated to 450 oC?

2.)  A pocket of gas is discovered in a deep drilling operation.  The gas has a temperature of 480 oC
and is at a pressure of 12.8 atm.  Assume ideal behavior.  What volume of the gas is required to
provide 18.0 L at the surface at 1.00 atm and 22 oC?

3.)  A fixed quantity of gas is compressed at constant temperature from a volume of 368 mL to 108
mL.  If the initial pressure was 5.22 atm, what is the final pressure?

4.)  A gas originally at 15 oC and having a volume of 182 mL is reduced in volume to 82.0 mL while its
pressure is held constant.  What is its final temperature?

5.)  At 36 oC and 1.00 atm pressure, a gas occupies a volume of 0.600 L.  How many liters will it
occupy at 0.0 oC and 0.205 atm?

6.)  What is the temperature at which 9.87 x 10-2 moles occupies 164 mL at 0.645 atm?

7.)  Chlorine is widely used to purify municipal water supplies and to treat swimming pool waters.
Suppose that the volume of a particular sample of Cl2 is 6.18 L at 0.90 atm and 33 oC.  What
volume will the Cl2 occupy at 107 oC and 0.75 atm?

8.)  A gas exerts a pressure of 1.5 atm at 27 oC.  The temperature is increased to 108 oC with no
volume change.  What is the gas pressure at the higher temperature?

Answers:  1.) 3.6 atm        2.) 3.59 L or 3.6 L            3.) 17.8 atm            4.) 130 K or 130. K
5.)
2.59 L or 2.6 L              6.) 13.1 K                           7.) 9.2 L                  8.) 1.9 atm

GAS STOICHIOMETRY (standard conditions)
** assume all reactions in this section occur at STP **
1.)  How many liters of oxygen can be formed from the decomposition of 2.00 grams of
KClO3.                                            __ KClO3
à __ KCl + __ O2

2.)  How many grams of CaCO3 are required to produce 6.00 L of CO2?
__ CaCO3
à __ CaO + __ CO2

3.)  Determine the volume of hydrogen gas produced when 0.250 moles of zinc react with
excess HCl.                                  __ Zn + __ HCl
à __ ZnCl2 + __ H2

4.)  How many liters of nitrogen are required to combine with 3.0 L of hydrogen in the
following reaction:                      __ N2 + __ H2
à __ NH3

5.)  How many liters of oxygen are needed to combine with 7.0 liters of propane in the
following reaction:                     __ C3H8 + __ O2
à __ CO2 + __ H2O

6.)  From the following reaction:             __ CH4 + __ O2 à __ CO2 + __ H2O
How many liters of CO2 are formed from 32.0 grams of CH4?

7.)  How many grams of Na are needed to produce 5.0 L of hydrogen?
__ Na + __ H2O
à __ NaOH + __ H2

8.)  Determine the volume of CO2 produced from burning 0.750 moles of C.
__ C + __ O2
à __ CO2

Answers:  1.) 0.551 L        2.) 26.8 g        3.) 5.60 L        4.) 1.0 L        5.) 35 L
6.)
44.8 L        7.) 10. g        8.) 16.8 L

DALTON’S LAW & GRAHAM’S LAW
1.
Determine the partial pressure of each gas in a container with 2.0 moles of N2, 3.0 moles
of O2, and 7.0 moles of H2 that has a total pressure of 850 mm Hg.  (You will have 3

2. A mixture of nitrogen and oxygen has a total pressure of 730 mm Hg. If the nitrogen has a
partial pressure of 420 mm Hg, find the pressure of the oxygen.

3. At an altitude of 30,000 ft., the total air pressure is only about 450. mm Hg.  If the air is
21.0 % oxygen, what is the partial pressure of oxygen at this altitude?

4. A mixture of 3 gases have the following pressures:  oxygen = 355 mm Hg, helium = 468
mm Hg, and nitrogen = 560 mm Hg.  Find the % of each gas in the mixture.

5. Compare the rate of effusion of CH4 and CO2.  (Give answers to # 5, 6, & 7 to 3 SF's.)
(Your answers for # 5, 6, &, 7 should read " ___  effuses ___ times faster than ___.")

6. Compare the rate of effusion of helium and nitrogen.

7. How much faster does ammonia (NH3) effuse than HCl?

8. An unknown gas effuses 4.0 times faster than O2.  Find the molar mass of the unknown
gas.  * What gas could this be?

Answers:    1.) N2 = 142 mm Hg, O2 = 213 mm Hg, H2 = 496 mm Hg        2.) 310 mm Hg
3.)
94.5 mm Hg        4.) O2 = 25.7%, He = 33.8 %, N2 = 40.5 %
5.) CH4 effuses 1.66 times faster than CO2.        6.) He effuses 2.65 times faster than N2.
7.) NH3 effuses 1.46 times faster than HCl          8.) 2.0 g/mole

UNIT 10 REVIEW WORKSHEET
1.)
Convert the following pressure measurements to atmospheres.
(A)  151.98 kPa                      (B)  456 mm Hg                         (C)  912 torr

2.) What are the conditions for gas measurement at STP?

3.) The volume of a sample of methane gas measures 350. mL at 27.0 oC and 810. mm Hg.  What is
the volume (in liters) at -3.0 oC and 650. mm Hg pressure?

4.) How many grams of nitrogen gas are contained in a 32.6 liter container at 34.4 oC and 579 torr?

5.) A mixture of four gases in a container exerts a total pressure of 955 mm Hg.  In this container,
there are 4.50 moles of nitrogen gas, 4.25 moles of carbon dioxide gas, 2.75 moles of hydrogen
gas, and 2.00 moles of oxygen gas.  What is the partial pressure of each gas?

6.) Compare the rates of effusion of carbon dioxide gas and carbon monoxide gas.

7.) An unknown gas effuses 1.37 times faster than chlorine gas.  What is the molar mass of the unknown gas?

8.) Given the following unbalanced reaction:
___ C5H12  +  ___ O2
à  ___ CO2  +  ___ H2O
How many liters of oxygen are needed to produce 45.7 liters of CO2?

9.) Given the unbalanced equation:
___ Mg  +  ___ O2
à  ___ MgO
How many liters of oxygen gas are required to produce 45.8 grams of magnesium
oxide?

10.) An aerosol can contains gases under a pressure of 4.50 atm at 20.0 oC.  If the can is left on a hot,
sandy beach, the pressure of the gases increases to 4.80 atm.  What is the temperature on the
beach (in oC)?

1.)  (A) 1.5003 atm   (B) 0.600 atm   (C) 1.20 atm
2.) 0 oC (or 273 K) & 1 atm                           3.) 0.393 L                     4.) 27.6 g
5.)
N2 = 318 mm Hg, CO2 = 301 mm Hg, H2 = 195 mm Hg, O2 = 141 mm Hg
6.) CO effuses 1.25 times faster than CO2.
7.) 37.8 g/mole                    8.) 73.1 L               9.) 12.8 L                 10.) 40.0 oC