CHAPTER 11 – IDEAL GAS LAW AND GAS STOICHIOMETRY 11.1- Mass and Volume of Gases Avogadro’s Principle = Equal volume of gases at same T and P have same numbers of molecules H2 He O2 N2 All of these balloons are the same size (same volume) All of these balloons are at the same Temperature and Pressure inside All of these balloons would have the same number of MOLECULES BUT…These balloons would have DIFFERENT masses! 11.1- Mass and Volume of Gases 1 mol of anything = 6.02 x 1023 particles 1 mol of any gas = same number particles = 6.02 x 1023 particles = same volume = different mass Molar Volume = Volume of 1 mole of any gas at STP 22.4 L = 1 mole of gas at STP 1 m ole 2 2 .4 L 22.4 L 1 m o le 11.1- Mass and Volume of Gases Examples: 11.1- Mass and Volume of Gases Gas Density -Depends on T and P -We will start by looking at density at STP dSTP = Molar Mass Molar Volume Examples: 11.1- Mass and Volume of Gases Examples: dSTP 11.1- Mass and Volume of Gases Molar Mass MM = dSTP * Molar Volume (will be given) 11.2 - Ideal Gas Law Used on ONE gas at ONE set of conditions PV = nRT Pressure Volume R = 0.08206 L atm /mol K = 62.4 L mmHg / mol K = 8.314 L KPa / mol K Temperature moles Ideal Gas Constant 11.2 - Ideal Gas Law How do you know which R to pick??? R = 0.08206 L atm /mol K = 62.4 L mmHg / mol K = 8.314 L KPa / mol K By the PRESSURE UNIT!! If Pressure is in mmHg… Pick 62.4 L mmHg / mol K If Pressure is in KPa… Pick 8.314 L KPa / mol K 11.2 - Ideal Gas Law Examples: 11.2 - Ideal Gas Law Examples: 11.2 - Ideal Gas Law Examples: Non-STP Gas Density d = MM * P R*T Examples: (will be given) Non-STP Molar Mass MM = mass sample * R * T P*V Examples: Will be given 11.3- Stoichiometry of Gases -NEED BALANCED EQUATION!! -Could include info from Chapter 3, 7,8,9, 10, or 11!! 11.3- Stoichiometry of Gases Review: Molar Mass from Periodic Table Grams A Moles A Ratio from Balanced Equation Moles B Molar Mass from Periodic Table Grams B New Information: With GASES…There are other options: Moles to Volume using 22.4L/mole at STP or PV=nRT Volume to Moles using 22.4L/mole at STP or PV=nRT 11.3- Stoichiometry of Gases Molar Mass from Periodic Table Grams A Moles A Ratio from Balanced Equation Moles B Molar Mass from Periodic Table 22.4 L/mol IF at STP 22.4 L/mol IF at STP OR OR PV=nRT if NOT STP PV=nRT if NOT STP Volume A if a GAS Volume B if a GAS Grams B 11.3- Stoichiometry of Gases Examples: 11.3- Stoichiometry of Gases Examples: 11.3- Stoichiometry of Gases Examples: 11.3- Stoichiometry of Gases Examples: