Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Boyle’s Law: The Volume-Pressure RelationshipSlide 8Slide 9Charles’ Law: The Volume-Temperature RelationshipSlide 11Standard Temperature and PressureCombining Boyle’s and Charles’s Laws: The General Gas LawSlide 14Slide 15Slide 16Avogadro’s HypothesisAvogadro’s HypothesisSlide 19Slide 20Summary of Gas Laws: The Ideal Gas LawSlide 22Summary of Gas Laws: The Ideal Gas LawSlide 24Slide 25Slide 26Slide 27Slide 28Slide 29Calculating the Molar Mass of a Gas from P, V and T DataSlide 31Slide 32Slide 3311.4 Gas Laws and Chemical ReactionsSlide 35Slide 36Slide 37Slide 38Slide 39Slide 40Slide 41Slide 4211.5 Gas Mixtures and Partial PressuresSlide 44Dalton’s Law of Partial PressuresMole FractionSlide 47Slide 48Slide 49Slide 5011.6 The Kinetic-Molecular Theory of GasesThe Kinetic-Molecular TheoryThe Kinetic-Molecular TheoryThe Kinetic-Molecular TheoryThe Kinetic-Molecular TheoryThe Kinetic-Molecular TheoryThe Kinetic-Molecular TheoryThe Kinetic-Molecular TheorySlide 59Slide 6011.7 Diffusion and EffusionDiffusion and Effusion of GasesDiffusion and Effusion of GasesSlide 64Slide 65Slide 66Slide 67Slide 6811.8 Nonideal Behavior of GasesReal Gases: Deviations from IdealityReal Gases: Deviations from IdealitySlide 72Slide 73Slide 74Ch 11 Gases and Their PropertiesSCUBA diving, Hot air balloons, automobile air bagsOnly need 4 quantities to describe most gases: Pressure (P), volume (V), temperature (T), and the amount of gas (n, moles), R .0821 L atm/mol KPV = nRTIdeal gas law1211.1 Gas PressurePressure is the force exerted on an object divided by the area over which it is exerted.•Pressure is force per unit area.–lb/in2 (psi)–N/m2•Atmospheric pressure is measured using a barometer.•Definitions of standard pressure (KNOW)76 cm Hg 760 mm Hg 760 torr1 atmosphere (atm) 101.3 kPa1.01325 bar 14.69 psiFig. 11-15, p. 531Hg density = 13.6 g/mLConversions:411.2 Gas Laws: The Experimental BasisBoyle’s Law: The Compressibility of GasesBoyle’s Law: The Volume-Pressure Relationship At a given T, the product of the pressure and volume of a definite mass of gas is constant.PV = k (constant n, T) T always in Kelvinhttp://www.grc.nasa.gov/WWW/k-12/airplane/aboyle.html good example56At 25oC a sample of He has a volume of 4.00 x 102 mL under a pressure of 7.60 x 102 torr. What volume would it occupy under a pressure of 2.00 atm at the same T? Think what it should be first.Known ValuesV1= 400 mLP1= 760 torr= 1 atmP=2 atmV2= ?7Boyle’s Law: The Volume-Pressure Relationship•Notice that in Boyle’s law we can use any pressure or volume units as long as we consistently use the same units for both P1 and P2 or V1 and V2.•Use your intuition to help you decide if the volume will go up or down as the pressure is changed and vice versa.What volume will 2.50 L of a gas occupy if the pressure is changed from 760. to 630. mm Hg?89The Effect of Temperature on Gas Volume: Charles’s Law (The Volume-Temperature Relationship)Charles’s law states that the volume of a gas is directly proportional to the absolute temperature at constant pressure.http://www.grc.nasa.gov/WWW/k-12/airplane/aglussac.html good onehttp://group.chem.iastate.edu/Greenbowe/sections/projectfolder/flashfiles/gaslaw/boyles_law_graph.html cool one can change volumehttp://www.nclark.net/GasLaws good website with lots of examplesGas laws must use the Kelvin scale to be correct.Relationship between Kelvin and centigrade.273 + C= K o10Charles’ Law: The Volume-Temperature RelationshipA sample of hydrogen, H2, occupies 1.00 x 102 mL at 25.0oC and 1.00 atm. What volume would it occupy at 50.0oC under the same pressure?V1=100 mLT1= 25C=298KP1= 1 atmV2=?T2= 50C= 323KP2=1 atm3.00 l of hydrogen at -20.°C is allowed to expand to 3.50 l. What is the temperature in °C? P is constant.1112Standard Temperature and Pressure•Standard temperature and pressure is given the symbol STP.–It is a reference point for some gas calculations. •Standard P = 1.00000 atm or 101.3 kPa•Standard T = 273.15 K or 0.00oC13Combining Boyle’s and Charles’s Laws: The General Gas Law•Boyle’s and Charles’ Laws combined into one statement is called the general (or combined) gas law equation.–Useful when the V, T, and P of a gas are changing. http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/gasesv6.swf awesome site for all gas laws22211122112211TV PTV P k TV P:is law gas combined The :gas of samplegiven aFor TVTV VPVPLaw Charles' Law sBoyle'Think about it!P = 1 atm, T = 280 K, V = 2.0 l, if you cool the gas and let it expand what will be the P? < or > 1 atm1415A sample of nitrogen gas, N2, occupies 7.50 x 102 mL at 75.00C under a pressure of 8.10 x 102 torr. What volume would it occupy at STP? Clicker Q: ST? In °C SP? In atmP1=810 torr V1= 750 mLT1= 75C= 348KP2= 1 atm= 760 torrV2=?T2= 273KGiven 20.0 l of ammonia gas at 5°C and 730. torr, calculate the volume at 50.°C and 800. torr.1617Avogadro’s Hypothesishttp://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/gasesv6.swf awesome site for all gas lawsAvogadro’s Hypothesis states that at the same temperature and pressure, equal volumes of two gases contain the same number of molecules (or moles) of gas.If we set the temperature and pressure for any gas to be STP, then one mole of that gas has a volume called the standard molar volume.18Avogadro’s Hypothesis•The standard molar volume is 22.4 L at STP.–This is another way to measure moles.–For gases, the volume is proportional to the number of moles. –11.2 L of a gas at STP = 0.500 mole–44.8 L19One mole of a gas occupies 36.5 L and its density is 1.36 g/L at a given temperature and pressure. (a) What is its molar mass? (b) What is its density at STP?2CO + 2 NO → 2CO2 + N20.20 moles of CO and 0.20 moles of NO occupy 15.0 l, what volume will products occupy?2021Summary of Gas Laws: The Ideal Gas Law•Boyle’s Law - V  1/P (at constant T & n)•Charles’ Law – V  T (at constant P & n)•Avogadro’s Hypothesis – V  n (at constant T & P)•Combine these three laws into one statementV  nT/P•Convert the proportionality into an equality.V = nRT/P •This provides the Ideal Gas Law.PV = nRT•R is a proportionality constant called the universal gas constant.22We must determine the value of R.–Recognize that for one mole of a gas at 1.00 atm, and 273 K (STP), the volume is 22.4