REVIEW QUESTIONS

Chapter 5

  1. Determine the pressure of the gas (in mmHg ) in the diagram below, given atmospheric pressure .
  2. A sample of oxygen gas has a volume of 26.7 L at 752 mmHg and . What is the volume of this gas at 1.30 atm and ?
  3. A 35.8 L cylinder of Argon gas is connected to and transferred into an evacuated tank at constant temperature. If the final pressure in the tank is 721 mmHg , what must have been the original pressure (in atm) in the cylinder?
  4. A cylinder contains 305 g of oxygen gas at . How many grams of gas must be released to reduce the pressure in the cylinder to 1.15 atm if the temperature remains constant?
  5. At STP, 0.280 L of a gas weighs 0.400 g . Calculate the molar mass of this gas.
  6. Calculate the density of HBr gas in at 733 mmHg and .
  7. A mixture of 4.00 g of hydrogen and 10.0 g of helium are in a flask at . What is the total pressure of the container and the partial pressures of each gas?
  8. Life rafts and weather balloons can be inflated by the reaction shown below:
How many grams of are needed to produce 10.0 L of hydrogen gas at 740 mmHg and ?
9. Nitroglycerin, an explosive compound, decomposes according to the equation below:
Calculate the total volume of gases produced at 1.2 atm and when 260 g of nitroglycerine is decomposed.
10. A sample of Al is reacted with excess HCl and the hydrogen produced is collected over water at at a barometric pressure of 744 mmHg . What volume of hydrogen gas is produced in this reaction? (Vapor pressure of water at is 23.8 mmHg )
11. Nitric oxide reacts with oxygen gas as shown below:
Initially NO and are separated as shown in the diagram below. When the valve is opened the reaction quickly goes to completion. Determine the identity of the gases that remain at the end of the reaction and their partial pressure. Assume temperature remains at .

12. A 4.85-g sample of solid ammonium chloride is placed in a evacuated flask and heated until it decomposes, as shown below:
After the reaction has completed, the total pressure in the flask is measured as 4.40 atm at . Based on this information, what percent of the ammonium chloride decomposed?
13. A mixture of gases containing 12.45 g of of and 2.38 g of are placed in a 10.00 L container at . What is the total pressure (in atm) and partial pressure of each component in the gas mixture?
14. Which has a higher average speed, at 150 K or He at ?
15. A big-league fastball travels at about . At what temperature ( ) do helium atoms have this same average speed?
16. The surface temperature of Venus is about 1050 K , and the pressure is about 75.0 earth atmospheres. Assuming that these conditions represent a Venusian "STP", what is the "standard" molar volume of a gas on Venus?
17. Gaseous iodine can be prepared by the reaction of solid iodine and gaseous fluorine:
A 5.00-L flask is charged with 10.0 g of and 10.0 g of , and the reaction proceeds until one of the reagents is completely consumed. After the reaction is complete the temperature in the flask is . What is the partial pressure of in the flask?
18. A sample of effuses from a container in 42.0 seconds. How long will it take the same amount of gaseous to effuse from the same container under identical conditions?
19. This reaction occurs in a closed container:
A reaction mixture initially contains 1.5 L of A and 2.0 L of B. Assuming that the volume and temperature of the reaction mixture is constant, how does the pressure change, and what is the percentage change if the reaction goes to completion.
20. A gas mixture contains and by mass. If the total pressure of this mixture is 0.44 atm , what is the partial pressure of each gas in the mixture?