7. A tire has a pressure of 1.02 atm and when the temperature rises to 42.1°C the pressure increases to 4.10 atm. What was the original volume of the tire?

8. A student finds that the air trapped in a tube occupies 32.2 mL at 0.654 atm. By adding mercury to
the tube, he increases the pressure on the trapped air to 0.975 atm. Determine the new volume of the
air.

9. A gas at 126.3 kPa and 90.0°C fills a flexible container with an initial volume of 6.00 L. If the
temperature is raised to 125.0°C and the pressure increased to 401.2 kPa. What is the new volume?

10. A balloon is filled with 2.75 L of air at 32.3°C and then placed in a car sitting in the sun. What is the
volume of the balloon when the temperature in the car reaches 76.4°C?

11. What is the molar mass of a sample of gas that has a density of 6.89 g/L at 205 kPa and 19.8°C?

12. A sample of nitrogen gas has a volume of 48.5 mL at a pressure of 0.888 atm and a temperature of
25.7°C. What volume will the hydrogen occupy at 2.47 atm and 52.3°C?