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1. How many grams of BF3 are present in 434-L at 2.2 atm and 788 K?
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2. How many grams of CH4 are in a vessel 8.75 Liters and at a temperature of 570 oC and at a pressure of 278.3 mm of Hg?
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3. What is the volume of a vessel that contains 8.17 grams of neon at 13 oC and at a pressure of 6635 Torr?
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4. What volume of carbon dioxide, measured at 200 oC and a pressure of 912 mm of Hg, will be formed upon combustion of 193.3 grams of butane, C4H10?
___ C4H10 + ___ O2  ___ CO2 + ___ H2O
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5. Calculate the density of sulfur dioxide gas at 40 oC and 730 mm of Hg?
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6. The density of a gaseous fluoride of phosphorous is 6.157 grams per Liter at STP.
a. Determine the molar mass of the compound.
b. Determine the molecular formula of the compound.
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7. A container has a volume of 3.2 m3 at 88 oC and a mixture of gases containing 1.5 grams of H2, 85.2 grams of O2, and 17 .0 grams of Ar.
First, what is the partial pressure of hydrogen gas?
Secondly, what is the total pressure in the vessel?
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8. A container has a volume of 5.37 Liters at 25oC and contains 0.0388 moles of O2, 0.147 moles of Ar, and 0.0803 moles of H2. What is the pressure in the flask?
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9. Calculate the ratio of the rates of effusion of He and Ar ?
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10. A gas of unknown identity diffuses at a rate of 83.3 mL/sec in an apparatus in which a second gas, carbon dioxide, diffuses at a rate of 102 mL/sec. Calculate the molar mass of the unknown gas.
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| 11. Two gases effuse from a container. The unknown gas requires only 29.9 minutes to effuse the same volume it takes carbon dioxide 37.3 minutes to effuse . What is the gram-molar mass of the unknown gas? |
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12. Aluminum metal reacts with dilute sulfuric acid to produce hydrogen gas. What volume of hydrogen gas at 24 oC and 743 mm Hg will be produced from 4.56 grams of Aluminum?
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13.Suppose we have two 1 Liter flasks, one containing N2 at STP, the other SF6 at STP. ow do these two systems differ with respect to
a. average kinetic energy of the molecules
b. average speed(velocity) of the molecules
c. total number of collisions with the container walls per unit time
d. the relative rates of effusion
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14. A 2.64 L vessel at 48 oC contains two moles of carbon dioxide experimentally is found to have a pressure of 18.4 atm. Calculate the pressure that would have been expected:
a. from the ideal gas equation
b. from the van der Waals equation.
van der Waals constant
a [L2atm/mole2]: 3.60 b [L/mole]: 0.0428
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15. A 35.4 L cylinder of oxygen gas at a pressure of 1.49 atm is changed so that the final pressure is 1.1 atm the temperature is held constant. What is the final volume?
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| 16. What is the volume of a sample of gas at 298 K and 1.1 atm if it occupies 40.5 mL at 467 K and 1.1 atm? |
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17. A student makes hydrogen gas by reacting zinc and dilute hydrochloric acid. The hydrogen gas was collected over water at temperature of 21.0 oC and a barometric pressure of 753.8 mm of Hg? The volume of gases was determined to be 0.567 Liter. What is the partial pressure of the water vapor and the partial pressure of the hydrogen gas.
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18. Explain why a latex balloon filled with helium gets smaller as time passes, but a latex balloon filled with sulfur hexafluoride gets bigger and bursts.
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