1. 7-XCDue at the time of SA 1. A sample of helium gas in a balloon has a volume of 10. L at a pressure of 0.90 atm. At 1.40 atm (T constant), is the new volume represented by A, B, or C? 2. For a cylinder containing helium gas, indicate if cylinder A or cylinder B represents the new volume for the following changes (n and T are constant): a) Pressure decreasesb) Pressure increases 3. A sample of hydrogen gas (H 2 ) has a volume of 5.0 L and a pressure of 1.0 atm. What is the new pressure if the volume is decreased to 2.0 L at constant temperature? 1 4. Solve Charles’ Law expression for T 2. V 1 = V 2 T 1 T 2

2. 5. A sample of neon gas has a volume of 5.40 L and a temperature of 15 ˚C. Find the new volume of the gas after the temperature has been increased to 42 ˚C at constant pressure. 6. A sample of oxygen gas has a volume of 420 mL at a temperature of 18°C. At what temperature (in °C) will the volume of the oxygen be 640 mL (P and n constant)? 1) 443°C2) 170°C 3) - 82°C 2 7. Aerosol containers can be dangerous if they are heated because they can explode. Suppose a container of hair spray with a pressure of 4.0 atm at a room temperature of 25 ˚C is thrown into a fire. If the temperature of the gas inside the aerosol can reaches 402 ˚C, what will be its pressure? The aerosol container may explode if the pressure inside exceeds 8.0 atm. Would you expect it to explode? 8. A weather balloon with a volume of 44 L is filled with 2.0 moles of helium. To what volume will the balloon expand if 3.0 moles of helium are added, to give a total of 5.0 moles of helium (the pressure and temperature do not change)?

3. 3 9. A gas has a volume of 675 mL at 35°C and 0.850 atm pressure. What is the volume(mL) of the gas at -95°C and a pressure of 802 mmHg (n constant)? 10. Dinitrogen oxide (N 2 O), laughing gas, is used by dentists as an anesthetic. If a 20.0 L tank of laughing gas contains 2.86 moles N 2 O at 23°C, what is the pressure in the tank? 11. In the following reaction, 81.2 mL of O 2 (g) is collected over water at 23 ˚C and barometric pressure 751 mmHg. What mass of Ag 2 O(s) decomposed?2 Ag 2 O(s)  4 Ag(s) + O 2 (g) Dalton’s law 1 st  Use Dalton’s law to find the partial pressure of O 2 Ideal Gas law 2 nd  Use the Ideal Gas law to find the moles of O 2 map 3 rd  Use the map to find grams of Ag 2 O