Gas Law Worksheet I

1. 3.00 moles of a gas are placed in a 4.55 L container at 245 °C. What is the pressure in kPa?

2. 65.85 grams of nitrogen gas are placed in 17.5 L container. The pressure is 1988 mm Hg. What is the temperature, in °C?

3. A gas is placed in a 2.00 L container at 25 °C and 550.0 mm Hg. The gas is now compressed to a volume of 0.75 L at constant temperature. What is the new pressure?

4. a) A gas is placed in a heavy container. The container is now heated. What happens to the gas and why?
   b) A gas is placed in a container with a moveable piston. It is then cooled down at constant pressure. What happens? Explain.
   c) A gas is placed in a container at a certain temperature and pressure. More gas is added and in order to keep the pressure and volume constant the temperature had to change. Was the container heated or cooled? Explain.

5. A gas is placed in a 3.45 L container at 45 °C and 2.7 atm. It is then compressed to a pressure of 8.25 atm and a volume of 0.550 L. What is the new temperature?

6. Butane (C₄H₁₀) is a fuel used in many lighters. The reaction is as follows:
   
   2 C₄H_{10 (g)} + 13 O_{2 (g)} --> 8 CO_{2 (g)} + 10 H₂O _(g)
   1. If 26.7 L of O₂ react at STP, how many liters of butane are needed at STP?
   2. 24.57 moles of water are formed. How many liters of butane were reacted at STP?
   3. 13.6 L of butane are reacted at STP, how many grams of carbon dioxide are formed?

7. 5.0 moles of a gas is put into a container of 2.0 L. More gas is added to the flask so that there is now 15 moles of the gas present. What must the new volume be if temperature and pressure are to remain constant?

8. A 7.0 L container is filled with 10.0 moles of a gas. The pressure is read at 4.00 atm, what is the temperature of the gas, in °C?

9. 3.0 L of a gas has a pressure of 12.0 atm. What is the new pressure if the gas is expanded to 17.0 L?

10. A gas is at 135 °C and 455 mm Hg in a 2.00 L container. It is cooled down to a temperature of 25 °C. If it is kept in the same container, what is its new pressure?

11. 155.0 grams of oxygen gas are put in a 4.50 L container at 35 °C. What is the pressure, in kPa?

12. A gas in a piston is heated up. If the pressure remains the same, what will happen to the volume? Why?

13. You went on a road trip to St. Louis (sea level) from Denver and made sure to check out your car before leaving. The tire pressures were at the recommended levels and your oil was full. You are driving fast through Kansas (but not above the speed limit of course) and need to stop for gas. You decide to check your car's tire pressure while stopped. The driver's manual suggests a pressure between 30 and 32 psi.
    1. Knowing that the tires heat up during driving, do you expect your reading to be high, low or the same as the recommended tire pressures? Why?
    2. You arrive in St. Louis that night. The next morning you check your tire pressure. Since you plan on staying in St. Louis a while to see the sights, what adjustments, if any, should be made to your tires?