Chem
Gas Laws Review
1. A gas effuses four times as fast as methane, CH4,. What is the molar mass of that gas?
2. Uranium hexafluoride is a gas used in uranium enrichment. In this process 235UF6 is separated from 238UF6 by the different mass of the two isotopes. If it takes 1000 seconds for a sample of 238UF6 to effuse through a hole, how long does it take a similar sample of 235UF6?
3. How many liters of F2 gas at 1000K and 20 atm pressure will react with 50g of uranium metal. Skeletal equation: U + F2 = UF6
4. How many grams of water will react with 10L of chlorine gas at 300K and 1.3 atm?
Cl2 + H2O = HClO + HCl
5. What volume will 25.0 g of oxygen gas occupy at 20.0˚C, and a pressure of 89.14 kPa?
6. A 2.00 liter sample of a gas originally at 25.0˚C, and a pressure of 1.00 atm, is allowed to expand to a volume of 5.00 liters. If the final pressure of the gas is 0.770 kPa, what is its final temperature?
7. A gas exerts a pressure of 0.329 atm at 20.0˚C. What pressure will it exert if its temperature is raised to 40.0˚C without change in volume?
8. A highly secretive flask of gasses contains 16.0 g of methane (CH4) and 16.0 g of Helium. The total pressure of the two gases is 0.567 atm and the temperature is 27.0oC. You may assume that the two gases do not react with each other.
- What is the number of moles of Helium in the flask?
- What is the partial pressure of Helium in the flask?
c. If the methane could be removed from the flask and the other conditions remained the same, what would be the total pressure exerted by the helium?
9. A mixture of N2 and O2 in a 0.200 liter container exerts a pressure of 0.948 atm at 35.0oC. If
there are 0.0020 moles of N2 present:
a. What is the partial pressure of N2?
b.What is the partial pressure of O2?
c. How many moles of O2 are present?
10. If four moles of a gas at a pressure of 5.4 atmospheres have a volume of 120 liters, what is the temperature?
11. If I initially have a gas with a pressure of 84 kPa and a temperature of 350 C and I heat it an additional 230 degrees, what will the new pressure be? Assume the volume of the container is constant.
12. My car has an internal volume of 2600 liters. If the sun heats my car from a temperature of 200 C to a temperature of 550 C, what will the pressure inside my car be? Assume the pressure was initially 760 mm Hg.
13. How many moles of gas are in my car in problem #3?
14. A toy balloon filled with air has an internal pressure of 1.25 atm and a volume of 2.50 L. If I take the balloon to the bottom of the ocean where the pressure is 95 atmospheres, what will the new volume of the balloon be? How many moles of gas does the balloon hold? (Assume T = 285 K)
15. For the reaction 2 H2(g) + O2(g) 2 H2O(g), how many liters of water can be made from 5 L of oxygen gas and an excess of hydrogen?
16. How many liters of water can be made from 55 grams of oxygen gas and an excess of hydrogen at STP?
17. How many liters of water can be made from 55 grams of oxygen gas and an excess of hydrogen at a pressure of 12.4 atm and a temperature of 850 C?
18. How many liters of water can be made from 34 grams of oxygen gas and 6.0 grams of hydrogen gas at STP? What is the limiting reactant for this reaction?
19. A gas sample is held at constant temperature and the pressure is cut by half. What happens to the volume?
20. A gas sample is held at constant pressure. The volume is doubled. What happens to the temperature?
21. A gas sample has some moles of gas in it. This number is doubled. How can we keep volume constant?
A. double temperature B. halve temperature C. double pressure D. halve pressure E. double pressure and halve temperature F. double temperature and halve pressure G. quadruple pressure and halve temperature H. quadruple temperature and halve pressure (More than one can be correct)