Gas Law Worksheet

Name _______________________________ Date__________________ Per. _____ Constants and Formulas (assume all variables not shown are constant) Pressure Unit Conversions 1 atm = 760 mmHg = 760 Torr = 101.325 kPa = 14.7 PSI K = oC + 273 Combined Gas Law P1V1 = P2V2 T1 T2 Constants Avogadro’s Law V 1 = V2 n1 n2 STP Standard T = 0 oC Standard P = 1 atm R = 8.314 L . kPa or mol . K 0.0821 L. atm mol . K Charles’ Law V1 = V2 T1 T2 Gay-Lussac’s Law P 1 = P2 T 1 T2 Boyle’s Law P 1V 1 = P 2 V 2 Molar volume: 22. 4 L/mol at STP Dalton’s Law of Partial Pressure P1 + P2 +…..Pn = Ptotal Answer on your own paper. SHOW ALL YOUR WORK, dimensional analysis and Given, Formula, Substitute, Solve. Circle final answers. Remember, temperatures must be in Kelvin and units must agree to cancel. Gas Law Problems Conversion Practice 1. Convert: 560 mmHg to atm and kPa. Boyle’s Law 1. A gas has a volume of 300 mL at 300 mm Hg. What will its volume be if the pressure is changed to 500 mm Hg? 2. A gas has a volume of 460 mL at 500. mm Hg. What will be the volume at 1.2 atm? 3. A gas has a volume of 5 liters at 3 atm. To expand the volume to 7500 ml, what the new pressure ( in atm ) have to be? Charles’s Law 4. A gas has a volume of 4.0 liters at 50. oC. What will its volume be (in liters) at 100. oC? 5. A gas has a volume of 350 mL at 45 oC. If the volume changes to 400 mL, what is the new temperature? ( answer in oC ) Gay-Lussac’s Law (Ammon’s Law) 6. The gases in a hair spray can are at a temperature of 27 oC and a pressure of 30 lbs/in2. If the gases in the can reach a pressure of 90 lbs/in2, the can will explode. To what temperature must the gases be raised in order for the can to explode? Assume constant volume. 7. Maybelline Cousteau’s backup oxygen tank reads 900 mmHg while on her boat, where the temperature is 27 oC. When she dives down to the bottom of an unexplored methane lake on a recently-discovered moon of Neptune, the temperature will drop down to –183 oC. What will the pressure in her backup tank be at that temperature? Combined Gas Law 8. A gas has a volume of 39 liters at STP. What will its volume be at 4.0 atm and 25 oC? 9. 400. mL of a gas is contained at 300. mm Hg and 0.00 oC. What will its volume be in mL at 140. mm Hg and 10.0 oC? 10. 500. mL of gas is contained at STP. The volume changes to 560 mL at 20. oC. What is the pressure (in atm)? Avogadro’s Law and Molar Volume at STP ( Remember 22.4 L/mol at STP ) 11. 50 g of nitrogen (N2) has a volume of ___ liters at STP. 12. 13. Consider the reaction: 2H2(g) + O2(g)  2H2O(g). What mass of oxygen is consumed at STP by 100. g H2? What volume of water forms if you have the exact stoichiometric ratio of hydrogen to oxygen ? Assume the reaction condition stays at STP throughout. What is the density of carbon dioxide at STP in two significant figures? Dalton’s Law Worksheet 14) A metal tank contains three gases: oxygen, helium, and nitrogen. If the partial pressures of the three gases in the tank are 35 atm of O2, 5 atm of N2, and 25 atm of He, what is the total pressure inside of the tank? 15) Blast furnaces give off many unpleasant and unhealthy gases. If the total air pressure is 0.99 atm, the partial pressure of carbon dioxide is 0.05 atm, and the partial pressure of hydrogen sulfide is 0.02 atm, what is the partial pressure of the remaining air? 16) If the air from problem 15 contains 22% oxygen, what is the partial pressure of oxygen near a blast furnace? Graham’s Law Problems 1) A certain gas effuses 4 times as fast as oxygen gas. What is the molar mass of the unknown gas? 2) A compound effuses through a porous cylinder 5.71 times slower than helium. What is it’s molar mass? Identify the compound. 3) If 0.00251 mol of NH3 effuse through a hole in 2.47 min, how much HCl would effuse in the same time? 4) A sample of N2 effuses through a hole in 38.00 seconds. What must be the molecular weight of gas that effuses in 60.45 seconds under identical conditions? Can you identify the gas?