GAS LAW MATH PROBLEMS

1. Helium takes up 5.71 liters at O°C and 3.95 atmospheres. What is the volume of the same helium at 320 K and 800 mmHg?

 

2. 257 mL of oxygen in a gas tube goes from 17°C to 42°C from being out in the sun. The pressure in the tube is 739 mmHg, but it does not change as the temperature increases. What is the volume of the tube after it has heated?

 

3. An enormous (57,400 cubic meter) expandable helium balloon at 22.0°C is heated up by a fire under it and the action of the sun on the dark plastic covering on top. There will be a small increase in pressure from 785 mmHg to 790 mmHg, but the major effect wanted is an increase in volume so the balloon can lift its cargo. To what temperature must the balloon get in order to fill out to 60,500 cubic meters?

 

4. What volume of air at standard pressure gets packed into an 11 ft³ SCUBA tank at the same temperature at 15.8 atmospheres? (Use SATP conditions as standard)

 

5. Air is 20% oxygen and 80% nitrogen. What is the mass of air in an automobile tire of 19.7 L and internal pressure of 46.7 PSI at 24°C? (That pressure is the same as the 32 PSI difference you usually measure as the tire pressure 32 PSI + 14.7 PSI. You will have to use a weighted average for the molar mass of air.)

 

6. A constant pressure tank of gas at 1.01 atm has propane in it at 15°C when it is at 255 cubic meters. What is its volume at 48°C?

 

7. A SCUBA tank is filled with air at 16.7 atm at 24°C, but someone leaves it out in the sun to warm to 65°C. What is the tank pressure?

 

8. The usual partial pressure of oxygen that people get at sea level is 0.20 atm., that is, a fifth of the usual sea level air pressure. People used to 1 atm. air pressure begin to become "light-headed" at about 0.10 atm oxygen. As a rule of thumb, the air pressure decreases one inch of mercury each thousand feet of altitude above sea level. At what altitude should airplane cabins be pressurized? Up to about what altitude should you be able to use unpressurized pure oxygen? (Express your answer in feet above Mean Sea Level, or MSL.)

 

9. Which diffuses faster, the bad smell from a cat-pan due to ammonia or an expensive French perfume with an average molecular weight of 170 g/mol? "How much faster does the faster one diffuse?

 

10. What is the mass of neon in a 625 mL neon tube at 357 mmHg & 25°C?

  11. Convert 110.55 C into K ?

12. What is the mass of 15 liters of chlorine gas at STP?

 

13. How many liters of ammonia at STP are produced when 10 g of hydrogen is combined with nitrogen?

 

14. How many milliliters of hydrogen at 0°C and 1400 mmHg are produced if 15g of magnesium reacts with sulfuric acid?

 

15. What is the mass of 25 liters of fluorine gas at 2.85 atm, 450°C?

 

16. A nine liter tank has 150 atmospheres of bromine in it at 27°C. What is the added mass of the tank due to the gas?

 

17. A 250 Kg tank of liquid butane (C4H1O) burns to produce carbon dioxide at 120°C. What volume of carbon dioxide is produced at 1 Atm?

 

18. How many liters of product at 950 mmHg and O°C is produced by the burning of three liters of acetylene (C2H2) at 5 atm and 20°C?

 

19. Five grams of octane (C8H18) and enough oxygen to burn it are in an automobile cylinder compressed to 20 atm at 28°C. The mixture explodes and heats the cylinder to 150°C. What is the pressure in the (same sized) cylinder after the explosion?

 

20. If 0.515g of magnesium is added to HCl, it makes hydrogen gas and magnesium chloride. The hydrogen is collected at 23°C and 735mmHg. What is the volume of hydrogen?

 

21. What is the mass of 150 liters of propane gas (C3H8) at 37°C and 245 in mmHg?

 

22. Isopropyl alcohol, C3H7OH , makes a good fuel for cars. What volume of oxygen at 735 mmHg and 23°C is needed to burn one kilogram of isopropyl alcohol?

 

23. What volume does 4 Kg of nitrogen gas take up at 27°C and 3 atm?

 

24. The dirigible Hindenberg had 3.7E6 m³ of hydrogen in its gas bags at 1.1 atm and 7°C. What was the weight of the hydrogen in pounds?