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1. An amazing scenehttp://www.youtube.com/watch?v=NWB0TrrjtAU&feature=related
2. HONOURS SPECIALIST -CHEMISTRY CONCEPT PRESENTATION TOPIC: IDEAL GAS LAW PRESENTER: VENKATA MOCHERLA DATE: 20TH JULY,2010 INSTRUCTIORS: JANINE EXTAVOUR & MARTY ZATZMAN
3. BACKGROUND INFORMATION: Ideal Gas Law is a concept that comes at the end of the Grade 11 university chemistry unit–F on Gases and Atmospheric Chemistry. This unit has covered all the fundamental concepts such as Matter, Energy, Structure and Function, Sustainability and Stewardship. Atmospheric chemistry is a branch of science that enables us to realize how and why our atmosphere is changing constantly.
4. Theory: Ideal Gas Law Ideal Gas: Gas does not condense to liquid when cooled Gas particles are point size ( volume of particle = 0) Gas particles do not attract each other V-T, P-T graphs are perfectly straight line Gas volume is zero at absolute zero. Ideal Gas Law: The product of the pressure and volume of a gas is directly proportional to the amount and the Kelvin temperature of the gas. PV = nRT Gas Constant (R):The constant of variation, R that relates the pressure in kPa, volume in L, amount in moles, and temperature in Kelvin of an ideal gas.
5. Numerical value of the Gas Constant: At STP 1.00 mol of an ideal gas would occupy a volume of 22.414 L V = 22.414 L n= 1.00 mol P = 101.325kPa T = 0°C or 273.15°K R = PV/nT R =101.325 kPa x 22.141 L 1.00 mol x 273.15°K R = 8.31 kPa.L/mol. °K
6. Big ideas: * properties of gases can be described qualitatively and quantitatively and can be predicted. *Air quality can be affected by natural calamities, human activities and technology.* People have a responsibility to protect the integrity of Earth’s atmosphere.
7. Overall expectations: *F1. Analyze the cumulative effects of human activities and technologies on air quality and describe some Canadian initiatives to reduce air pollution, including ways to reduce their own carbon footprint.* F2. Investigate gas laws that explain the behaviour of gases and solve related problems.*F3. Demonstrate an understanding of the laws that explain the behaviour of gases.
8. Specific Expectations: *F1.1 Analyze the effects on air quality of some technologies and human activities. [propose actions to reduce their personal carbon footprint]. [AI,C]*F1.2 Assess air quality conditions for a given Canadian location, using Environment Canada’s Air Quality Health Index, and report on some Canadian initiatives to improve air quality and reduce green house gases. [Ontario’s Drive Clean Program to control vehicle emissions, 3person lanes for heavy traffic roads, bike lanes]. [AI,C]*F2.1 Use appropriate terminology related to gases and atmospheric chemistry. *F2.2. Determine the quantitative relationship between the pressure, volume, temperature and moles.*F2.3 Solve problems by performing calculations based on the Ideal Gas Law. *F3.3 Use the kinetic molecular theory to explain the properties and behaviour of gases in terms of types and degrees of molecular motion. *F3.4 Describe for an ideal gas, the quantitative relationships that exist between the variables of pressure, volume, temperature and amount of substance.
9. Misconceptions: Misconception # 1:Students often confuse air with empty space. Make sure that students understand that there is empty space between the particles of air.
10. Misconception#2: Student often confuse between Ideal Gas and Real Gas. An ideal gas is the one that satisfies all the assumptions of the kinetic-molecular theory – such as particles do not experience attractive forces, total volume of the actual particles is negligible compared to the volume of the gas itself. A real gas is the one that experience forces of attraction at high pressures. Volume become a significant proportion of the total volume at low temperature. * Real gases behave like an Ideal Gas when their temperature is increased and their pressure is decreased.
11. Misconception # 3:Students often confuse with STP and SATP STP: Standard Temperature and Pressure measured at sea level.Temperature is = 0°C and Pressure is 101.325kPaSATP: Standard Ambient Temperature and Pressure [room temperature and pressure]Temperature is 25°C and Pressure is 100kPaMisconception#4:Students often confuse between pressure and forcePressure is force applied on unit area. [ P = F/A]
12. Student learning difficulties: #1. Students use the ideal gas law [ PV = nRT] assuming that one variable is either directly or inversely proportional to another without considering that this only works if all other variables are constant. Students believe that P is always inversely proportional to V when this only works when n and T are constant. Students believe that P is always directly proportional to T when this only works when n and V are constant. #2. Students always has a difficulty in rearranging the formulas PV = nRT V = nRT P= nRT n = PV P V RT
13. Student learning difficulties #3 .Students could be inconsistent with the units including absolute zero.[lowest possible temperature 0°K or -273°C]#4 .Students have difficulty understanding the behaviour of gas particles microscopically. E.g. They usually say that the rubber walls of the balloon stop it from expanding and rarely say that the air particles outside the balloon hit the walls in the opposite direction. #5.Molar Volume: the volume that one mole of a gas occupies at a specified temperature and pressure.VSTP = 22.4L/mol; VSATP= 24.8 L/mol
14. Curriculum connections
15. Possible Assessment and Evaluation Tools Assessment for Learning: Jeopardy game for knowing their knowledge levels in Boyle’s Law, Charles Law, Gay-Lusacc’s Law, Combined Gas Law. Hook: popcorn popping Assessment as Learning: Investigation activity: Determining the Molar Mass of a Gas using the Ideal Gas Equation. Assessment of Learning: Lab: Finding the Gas Law Constant.
16. Advance preparation by Teacher Online video clippings need laptop, projector, speakers and screen are needed. So teacher has to make these arrangements in advance. For demonstrations and investigations and summative lab required materials like popcorn maker, corn kernel, butane lighters [with out flint], water troughs, measuring cylinders, electronic balance, alka seltzer tablets thermometer, barometer, balloons, test tubes are to be kept ready. All word problem solving work sheets, investigation work sheets and summative lab work sheets are to be photocopied and kept ready.
17. Safety considerations There are no big safety issues for this particular topic but still students need to follow the safety procedures of the lab such as wearing safety goggles, tying up long hair, if any injuries or spills immediately report to teacher and so on. For the investigation activity butane gas is used, so it is to be disposed in the fume hood or outdoors.
18. Lesson Sequence: Day 1: Hook: popcorn popping. Reinforcing concepts–Boyle’s Law, Charles Law, Gay-Lussac Law, Combined Gas Law (Jeopardy game) Work sheet on Kinetic molecular theory Problem solving work sheet. Strategies: *Teacher demo followed by discussion questions. Teacher conducts the jeopardy game by dividing students into groups. Students would work problems on white board. Differentiated Instruction: Hook popcorn popping would give them the relation between temperature, pressure and volume and the combined gas law. Jeopardy game would motivate the students to reinforce their understanding. Learning Styles: Verbal, visual, logical/mathematical, kinaesthetic, inter-personal and ELL
19. Day:2 Investigation Activity –Cooperative Group Learning. Students would work in groups of 3. [manager, reporter, speaker] Problem handout and instructions handout will be given to students. Students will gather the material, set up the material and perform the activity. Students follow the problem solving strategy:- Strategies: student directed activity. Teacher would be observing and helping the students if any need. Scaffolding the activity. Differentiated Instruction: Process: level of scaffolding, working in small groups, Learning Styles: Verbal, visual, logical/mathematical, kinaesthetic, inter-personal and ELL Problem statement Describe the problem Define chemistry Plan the solution Execute the plan Evaluate the answer
20. Day 3 Reinforcement of Ideal Gas Law:- Strategies: videos on Ideal Gas Law. http://www.teachertube.com/viewVideo.php?video_id=132580 http://www.youtube.com/watch?v=zjv0zGkxXPI&feature=related Song for solving problems on Ideal Gas Law. Problem solving work sheets. Differentiated Instruction : use of videos to reinforce the Ideal Gas Law. Song for reinforcing the problem solving skills. Problem solving worksheets with different difficulty levels. Learning Styles : Verbal, visual, logical/mathematical, kinaesthetic, inter-personal, and ELL
21. Day-4 Students perform their summative lab in groups of 3 . Lab instructions and expectations handout will be given two days in advance. Students will make a pre-lab report and take teacher approval to perform the lab. Students follow the safety rules and procedures and perform the lab. And complete all the data sheets with required information and readings. Finally make the formal (APA format) lab report and complete the analysis and discussion questions by following the achievement rubric sheet. Students submit the lab report as per the teacher’s instructions on the due date. Differentiated Instruction : Extra time for ELL and IEP students, more simplified analysis and discussion questions. Learning Styles: Verbal, visual, logical/mathematical, kinaesthetic, inter-personal, and ELL
22. Applications and societal implications: This unit has a great significance in the applications and societal implications as it is mainly dealt with the behaviour of different gases and chemistry behind them. Right from popping of popcorn to huge volcanic eruptions From pressure cookers to natural geysers From tornados to tsunamis From propane gas cylinders to spray cans From Scuba diving to submarines From bike tires to airplane wheels From helium balloons to weather parachutes From oxygen cylinders to commercial gases transportation Most amazing breathing and body mechanisms in living beings Whether it is pressure, volume ,temperature or moles Name it as Boyle’s Law or Charles Law Gay-Lussac’s Law or Dalton’s Law Combined Gas Law or Ideal Gas Law WOW! What a discovery by those scientists Made us to understand better about the environment Remind us to feel the responsibility to protect it and preserve it To make this world a better place to live in.
23. Annotated References: http://www.youtube.com/watch?v=NWB0TrrjtAU&feature=related This is an amazing video from ytube http://www.youtube.com/watch?v=zjv0zGkxXPI&feature=related http://www.nclark.net/GasLaws#Links Geoff Rayner-Canham, Sadru Damji, Ute Goering-Boone. (2001) Addison Wesley Chemistry 11 text book by Pearson Education Canada Inc, Toronto, Ontario. Cheryl Wistrom, John Phillips, Victor Strozak, (1997), Teacher Wraparound Edition, Chemistry Concepts and Applications by Glencoe, McGraw-Hill, printed in United States of America. Dr. Frank Jenkins, Hans van Kessel, Lucille Davies, Dr. Oliver Lantz, Patricia Thomas, Dick Tompkins,(2002) Nelson Chemistry 11 by Nelson Thompson Learning , printed and bounded in Toronto Canada. Alka Seltzer lab and Ideal gas contributed by "Rosemarie Smith" <rsmith@fc.wtvl.k12.me.us>
24. Acknowledgments Firstly my sincere thanks goes to Janine and Marty who are my instructors for their excellent inspired lectures and demonstrations. My honest thanks to all the participants in this Honours specialist course for their valuable presentations of either basic practices or concept presentations. My humble thanks to my mentor Initha for her valuable suggestions. Last but not the least my whole hearted thanks to the human brains who has invented this computer for this presentation without this technology it would not have been possible for me to engage you learned intellectuals for these 45 minutes.