Chemistry Lab By Linda Wozniewski
What do they need to be able to do every year every year? Interpretation of experimental data (tabular and/or graphic) Observation of an experiment set up and running Computer or calculator sensors/probes Stoichiometry : mole conversions and percentage yield Stoichiometry : mole conversions and percentage yield Nomenclature and formula writing - symbols and charges for the following ions by memory: nitrate, carbonate, phosphate, acetate, sulfate, ammonium, bicarbonate, and hydroxide (“ite” forms of “ates” listed)
Safety Students must wear: Closed shoes Closed shoes Slacks or skirts that come to the ankles Slacks or skirts that come to the ankles Sleeved shirts Sleeved shirts Lab coat or lab apron Lab coat or lab apron Indirect vent or unvented chemical splash proof goggles. No impact glasses or visorgogs are permitted Indirect vent or unvented chemical splash proof goggles. No impact glasses or visorgogs are permitted
What the Students Should Bring Safety gear Something to write with What the Students Should Not Bring Anything else This includes notes
What the Supervisor Provides Everything the student will need
How to prepare participants Make sure students read the directions and pay particular attention to the description of the event (The Competition) Have them do many experiments together Have them determine their individual strengths Divide (and conquer) tasks during competition Check each other’s work
How to prepare participants Get as many lab books from your chemistry teacher as possible & have students explore labs by topic and do the ones that appear consistently
Changes for new topics: Kinetics Kinetics Aqueous Solutions Aqueous Solutions
Kinetics Students will demonstrate an understanding of the principals of kinetics. They must be able to measure reaction rates and identify how and why reaction conditions (temperature, concentration, particle size, and catalysts) affect reaction rates. At the regional level, teams will NOT be asked to determine rate laws experimentally or from data provided. At the state and national levels, teams will be asked to determine rate laws from actual experimentation or data provided, and teams should also be able to determine rate constants with correct units
Kinetics Calculating a rate Fair game at Regional Competitions Fair game at Regional Competitions [] means the concentration of [] means the concentration of Rate Law Can only be done at State and National Can only be done at State and National Rate = k[A] x [B] y … Rate = k[A] x [B] y …
Kinetic Activities Iodine Clock Reaction – one of the most famous & widely used kinetic reactions Very easy to do, but very hard to explain all of the chemistry A/CCA3/MAIN/CLOCKRX/PAGE1.HTM A/CCA3/MAIN/CLOCKRX/PAGE1.HTM For a really cool oscillating reaction (if you have the resources) ons/a/aa050204a.htm
Kinetic Activities To see the effects of surface area Reaction of Powdered Sugar and Granular Sugar with concentrated H 2 SO 4 omy/transitvenus/sugarsulfuricacid.htm
Kinetic Activities To see the effects of concentration on kinetics, try Reaction of mossy zinc in 2 M CuSO 4 &.2 M CuSO 4
Kinetics Activities To see the effect of temperature, try a simple baking soda and vinegar experiment at different temperatures.
Kinetics Activities y/a/reactionrate.htm
Aqueous Solutions Students will demonstrate an understanding of the principals and properties of aqueous solutions. They must be able to calculate solution concentrations given quantities of solute and solvent, and to calculate quantities of material required to produce a solution of specified concentration. Molarity, molality, mass percentage, and parts per million may be required. Students are also required to demonstrate an understanding of colligative properties. At the state and national levels, conversions between concentration units may be required.
Aqueous Activities Use the concept of density to experimentally determine the concentration of a solution. Determine solution concentration using a series of standard absorbencies and Beer’s Law. Use freezing point depression to determine the molar mass of a solute. Use titration to determine an unknown concentration. Identify and explain factors that effect solution formation. Construct a solubility curve. Determine whether a solution is saturated, unsaturated or supersaturated
Aqueous Activities /library.thinkquest.org/10429/low/sol/sol. htm
Resources: TI Activity Exchange vityexchange/BrowseResult.do?cid=US&s ubName=Science&subAreaName=Chemis try&subAreaId=5028&catName=Kinetics& catId=1097&aCount=6&brsOpenNode=bt1.o%2816%29
Scoring 50% Kinetics 50% Aqueous Solutions
Questions????? Thank you