Gas Laws Review Sheet

Gas Laws Review Sheet Definitions: 1. Boyle’s Law – states that as the pressure of a gas increases the volume decreases 2. Charles’ Law – states that as the temperature of a gas increases the volume also increases 3. Dalton’s Law of Partial Pressures – states that the sum of the partial pressures of individual gases is equal to the total pressure in a container Formulas: 4. What is the formula for the combined gas law? P1V1 = P2V2 T1 T2 5. What is the formula for the ideal gas law? PV = nRT 6. What is the value for R in the ideal gas law? 8.31 L∙kPa / K∙mol 7. What does R stand for in the ideal gas law? the ideal gas law constant 8. What does n stand for in the ideal gas law? the number of moles Short Answer: 9. What happens to the volume of a gas if the temperature is increased? the volume increases 10. What happens to the volume of a gas if the temperature is decreased? the volume decreases 11. What happens to the volume of a gas if the pressure is increased? the volume decreases 12. What happens to the volume of a gas if the pressure is decreased? the volume increases 13. What happens to the pressure of a gas if the temperature is increased? the pressure increases 14. What happens to the pressure of a gas if the temperature is decreased? the pressure decreases Calculations: 15. If 3.2 moles of a gas are at a temperature of 300 K and a volume of 83.8 L, what is the pressure of the gas? P = nRT V P = 3.2 x 8.31 x 300 83.8 P = 95 kPa 16. If 2.4 L of gas is at a pressure of 387 kPa, what would the pressure be if the volume was expanded to 29.8 L? P2 = P1V1 V2 P2 = 387 x 2.4 29.8 P2 = 31 kPa 17. Argon occupies a volume of 28.3 L at a pressure of 50 kPa. Find the volume of argon when the pressure is increased to 310 kPa. V2 = P1V1 P2 V2 = 50 x 28.3 310 V2 = 4.6 L 18. A rigid container of oxygen gas has a pressure of 180 kPa at a temperature of 351 K. What is the pressure at 193 K? P2 = P1T2 T1 P2 = 180 x 193 351 P2 = 99 kPa 19. A gas has a pressure of 180 kPa at 120°C. What will the pressure be at 30°C if the volume does not change? P2 = P1T2 T1 P2 = 180 x 303 393 P2 = 139 kPa 20. A balloon containing 150 L of gas at 52°C and 101.3 kPa rises to an altitude where the pressure is 62.1 kPa and the temperature is -20°C. What would the volume become at this new altitude? V2 = P1V1T2 T1P2 V2 = 101.3 x 150 x 253 (325 x 62.1) V2 = 190 L 21. A plastic bottle contains 32.5 L of gas at a pressure of 45.7 kPa and is compressed to a volume of 4.1 L. What would be the new pressure? P2 = P1V1 V2 P2 = 45.7 x 32.5 4.1 P2 = 362 kPa 22. How many moles of nitrogen gas are in a flask with a volume of 24 L at a pressure of 320 kPa and a temperature of 87°C? n = PV RT n = 320 x 24 (8.31 x 360) n = 2.6 moles 23. If a gas at 35.0°C is pressurized from 160 kPa to 250 kPa, what would be the final temperature? T2 = T1P2 P1 T2 = 308 x 250 160 T2 = 481 K 24. What is the volume of 0.91 moles of oxygen gas at 214°C and 865 kPa? V = nRT P V = 0.91 x 8.31 x 487 865 V = 4.3 L 25. A balloon has a volume of 43.6 L at 310 K. What is the temperature of the balloon if the volume is decreased to 27.8 L? T2 = T1V2 V1 T2 = 310 x 27.8 43.6 T2 = 198 K 26. A breathing mixture used by deep sea divers contains helium, oxygen and carbon dioxide. If oxygen exerts a pressure of 35 kPa, helium exerts a pressure of 52 kPa and carbon dioxide exerts a pressure of 1.5 kPa, what is the total pressure? PTOTAL = P1 + P2 + P3 PTOTAL = 35 + 52 + 1.5 PTOTAL = 88.5 kPa