Gas Behavior: Not Just Laws, It’s a Good Idea
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Gas Behavior: Not Just Laws, It’s a Good Idea Eric Grunden Raleigh Charter High School NCSTA Nov. 11, 2011
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Gas Behavior: Not Just Laws, It’s a Good Idea. Eric Grunden Raleigh Charter High School NCSTANov. 11, 2011. What’s the point of all this? Teach more by teaching less. What? That sounds like Zen nonsense. What else is being presented now? What am I going to learn from this? - PowerPoint PPT Presentation
Transcript of Gas Behavior: Not Just Laws, It’s a Good Idea
Gas Behavior: Not Just Laws, Its a Good Idea
Gas Behavior:Not Just Laws, Its a Good IdeaEric GrundenRaleigh Charter High SchoolNCSTANov. 11, 2011
Whats the point of all this?Teach more by teaching less.What? That sounds like Zen nonsense. What else is being presented now? What am I going to learn from this?Something to help your students really get gas behaviorInquiry activitiesHigh cognitive level instruction ideasDo I get free stuff?Maybe.
While hes talking, watch this movie of a crab being pushed into an underwater pipe by a pressure gradient.
DONT TEACH THE GAS LAWS.
Really.
DONT TEACH THE GAS LAWS.
Really.
Too much memorizing without understanding.Too much work for you as a teacher.Too much stuff to learnEmphasizes namesCan be wrong
Robert BoyleIm sceptical of this.(but then, my Facebook page is run by the Institute for Creation Research)
Je suis Joseph Gay-Lussac!
Je suis Jacques Charles!
Je suis Guillaume Amontons!Qui?
The Kinetic Theory of GasesBuild a mechanical understanding of gas behavior.Have students build a kinetic theory from observation.Observe the simulation, note behaviors, and combine results, looking for the common observations.All gas behavior can be described from the 5 principlesGas particle volume is insignificantParticles move in constant, random, straight-line motionSpeed is proportional to temperatureCollisions are elasticNo forces act between particlesBetter Living through Simulations
How much space is between molecules?
These peanut butter cups would be 242 meters apart if they were He atoms at room temperature.(radius of a He atom: 31 pm; 3nm between He atoms at room temperature)
Describe the four measurable characteristics of gases:
Pressure: collisions with container walls (how hard, how often)
Volume: distance traveled by particles
Temperature: kinetic energy of particles (speed, as long as not comparing different gases)
Number of particles: well, the number of particles
This is a good time for sketching!This is a good time for small groups discussing effects of changing these conditionsAll explanations MUST BE in terms of molecular motion, not a gas law.
OK, I lied.
Teach ONE gas law:PV = nRT(For fun you can introduce non-ideal gases.)
The important thing is to
Build the mechanical understanding of simple gas behaviorsThen APPLY that knowledge.
Prove the named gas lawsFind the molecular weight of butaneJobs Method
Student gas law projects
The best gas demo material ever:
Balloon-fillingStoichiometryDemonstrating the Greenhouse Effect
Chart129326447.753.714.4
Volume (cubic inches)Moles of CO(2)Volume (cubic inches)Volume As a Function of Moles of CO(2)
Sheet1Moles of CO2Volume (cubic inches)0.0882930.0622640.0247.70.01753.70.00514.4
Sheet100000
Volume (cubic inches)Moles of CO(2)Volume (cubic inches)Volume As a Function of Moles of CO(2)
Sheet2
Sheet3
