chemistry lab by linda wozniewski [email protected]. what do they need to be able to do every year every...
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What do they need to be able to do What do they need to be able to do every year every year? every year every year?
Interpretation of Interpretation of experimental data experimental data (tabular and/or graphic) (tabular and/or graphic)
Observation of an Observation of an experiment set up and experiment set up and running running
Computer or calculator Computer or calculator sensors/probes sensors/probes
Stoichiometry : mole Stoichiometry : mole conversions and conversions and percentage yieldpercentage yield
Nomenclature and Nomenclature and formula writing - symbols formula writing - symbols and charges for the and charges for the following ions by memory: following ions by memory: nitrate, carbonate, nitrate, carbonate, phosphate, acetate, phosphate, acetate, sulfate, ammonium, sulfate, ammonium, bicarbonate, and bicarbonate, and hydroxide (“ite” forms of hydroxide (“ite” forms of “ates” listed) “ates” listed)
SafetySafety
Students must wear:Students must wear: Closed shoesClosed shoes Slacks or skirts that come to the anklesSlacks or skirts that come to the ankles Sleeved shirtsSleeved shirts Lab coat or lab apronLab coat or lab apron Indirect vent or unvented chemical splash Indirect vent or unvented chemical splash
proof goggles. No impact glasses or proof goggles. No impact glasses or visorgogs are permittedvisorgogs are permitted
What the Students Should BringWhat the Students Should Bring
Safety gearSafety gear
Something to write withSomething to write with
What the Students Should Not BringWhat the Students Should Not Bring
Anything else
This includes notes
What the Supervisor ProvidesWhat the Supervisor Provides
Everything the student will needEverything the student will need
How to prepare participantsHow to prepare participantsMake sure students read the directions and pay Make sure students read the directions and pay particular attention to the description of the particular attention to the description of the event (The Competition) event (The Competition)
Have them do many experiments together Have them do many experiments together
Have them determine their individual strengths Have them determine their individual strengths
Divide (and conquer) tasks during competition Divide (and conquer) tasks during competition
Check each other’s work Check each other’s work
How to prepare participantsHow to prepare participants
Get as many lab books from your Get as many lab books from your chemistry teacher as possible & have chemistry teacher as possible & have students explore labs by topic and do the students explore labs by topic and do the ones that appear consistently ones that appear consistently
Changes for 2009 Changes for 2009
2 new topics: 2 new topics: KineticsKinetics Aqueous Solutions Aqueous Solutions
KineticsKineticsStudents will demonstrate an understanding of Students will demonstrate an understanding of
the principals of kinetics. They must be able the principals of kinetics. They must be able to measure reaction rates and identify how to measure reaction rates and identify how and why reaction conditions (temperature, and why reaction conditions (temperature, concentration, particle size, and catalysts) concentration, particle size, and catalysts) affect reaction rates. At the regional level, affect reaction rates. At the regional level, teams will NOT be asked to determine rate teams will NOT be asked to determine rate laws experimentally or from data provided. laws experimentally or from data provided. At the state and national levels, teams will be At the state and national levels, teams will be asked to determine rate laws from actual asked to determine rate laws from actual experimentation or data provided, and teams experimentation or data provided, and teams should also be able to determine rate should also be able to determine rate constants with correct unitsconstants with correct units
KineticsKinetics
Calculating a rateCalculating a rate Fair game at Regional CompetitionsFair game at Regional Competitions
[] means the concentration of[] means the concentration of
Rate LawRate Law Can only be done at State and NationalCan only be done at State and National Rate = k[A]Rate = k[A]xx[B][B]yy……
time
reagent] [limiting Rate
Kinetic Activities Kinetic Activities Iodine Clock Reaction – one of the most Iodine Clock Reaction – one of the most famous & widely used kinetic reactionsfamous & widely used kinetic reactions
Very easy to do, but very hard to explain Very easy to do, but very hard to explain all of the chemistryall of the chemistry
http://jchemed.chem.wisc.edu/JCESoft/CCA/CCA3/MAIN/CLOCKRX/PAGE1.HTM
For a really cool oscillating reaction (if you For a really cool oscillating reaction (if you have the resources)have the resources)
http://chemistry.about.com/cs/http://chemistry.about.com/cs/demonstrations/a/aa050204a.htmdemonstrations/a/aa050204a.htm
Kinetic ActivitiesKinetic Activities
To see the effects of surface area To see the effects of surface area
Reaction of Powdered Sugar and Granular Reaction of Powdered Sugar and Granular Sugar with concentrated HSugar with concentrated H22SOSO44
http://www.exo.net/~pauld/activities/http://www.exo.net/~pauld/activities/astronomy/transitvenus/astronomy/transitvenus/sugarsulfuricacid.htmsugarsulfuricacid.htm
Kinetic ActivitiesKinetic Activities
To see the effects of concentration on To see the effects of concentration on kinetics, trykinetics, try
Reaction of mossy zinc in 2 M CuSOReaction of mossy zinc in 2 M CuSO44 & .2 & .2
M CuSOM CuSO44
Kinetics ActivitiesKinetics Activities
To see the effect of temperature, try a To see the effect of temperature, try a simple baking soda and vinegar simple baking soda and vinegar experiment at different temperatures.experiment at different temperatures.
Kinetics ActivitiesKinetics Activities
http://chemistry.about.com/od/http://chemistry.about.com/od/stoichiometry/a/reactionrate.htm stoichiometry/a/reactionrate.htm
Aqueous SolutionsAqueous SolutionsStudents will demonstrate an understanding of the Students will demonstrate an understanding of the principals and properties of aqueous solutions. principals and properties of aqueous solutions. They must be able to calculate solution They must be able to calculate solution concentrations given quantities of solute and concentrations given quantities of solute and solvent, and to calculate quantities of material solvent, and to calculate quantities of material required to produce a solution of specified required to produce a solution of specified concentration. Molarity, molality, mass concentration. Molarity, molality, mass percentage, and parts per million may be required. percentage, and parts per million may be required. Students are also required to demonstrate an Students are also required to demonstrate an understanding of colligative properties. At the understanding of colligative properties. At the state and national levels, conversions between state and national levels, conversions between concentration units may be required.concentration units may be required.
Aqueous ActivitiesAqueous ActivitiesUse the concept of density to experimentally Use the concept of density to experimentally determine the concentration of a solution.determine the concentration of a solution.Determine solution concentration using a series of Determine solution concentration using a series of standard absorbencies and Beer’s Law.standard absorbencies and Beer’s Law.Use freezing point depression to determine the Use freezing point depression to determine the molar mass of a solute.molar mass of a solute.Use titration to determine an unknown concentration.Use titration to determine an unknown concentration.Identify and explain factors that effect solution Identify and explain factors that effect solution formation.formation.Construct a solubility curve.Construct a solubility curve.Determine whether a solution is saturated, Determine whether a solution is saturated, unsaturated or supersaturated unsaturated or supersaturated
Aqueous ActivitiesAqueous Activities
http://chemtutor.com/mols.htm#dv
http://web.archive.org/web/http://web.archive.org/web/20070505005726/library.thinkquest.org/20070505005726/library.thinkquest.org/10429/low/sol/sol.htm10429/low/sol/sol.htm
Resources: TI Activity Exchange Resources: TI Activity Exchange
http://education.ti.com/educationportal/http://education.ti.com/educationportal/activityexchange/BrowseResult.do?activityexchange/BrowseResult.do?cid=US&subName=Science&subAreaNamcid=US&subName=Science&subAreaName=Chemistry&subAreaId=5028&catName=e=Chemistry&subAreaId=5028&catName=Kinetics&catId=1097&aCount=6&brsOpenKinetics&catId=1097&aCount=6&brsOpenNode=bt1.o%2816%29Node=bt1.o%2816%29