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ENTHALPY OF FORMATION: Combustion of Methanol. River Dell High School Team A Jason Anesini Alina Kim Jae Noh. PURPOSE. To construct an alcohol/hydrocarbon-fueled combustion reactor that propels a stopper upwards
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ENTHALPY OF FORMATION:Combustion of Methanol River Dell High School Team A Jason Anesini Alina Kim Jae Noh
PURPOSE • To construct an alcohol/hydrocarbon-fueled combustion reactor that propels a stopper upwards • To determine the optimal way of measuring the energy released in the combustion reaction • To determine the enthalpy of formation of methanol
EVERYDAY COMBUSTION • Fireworks • Charcoal • Car engines • Gasoline
COMBUSTION • What is combustion? • CH3OH(l) + 3/2O2(g) CO2(g) + 2H2O(g)
ENTHALPY • Heat of formation • ∆H when one mole of a compound is formed from its elements • Standard heat of formation • Heat of combustion • Heat released in a combustion reaction
METHANOL • Synthesized from CO and H2 • Used as energy source and in many everyday appliances • Lowest Eaamong alcohols • Costs 3x less than ethanol
EXPERIMENT APPARATUS • Stopper – with green line • Methanol (stored in Drierite) • Nalgene bottle (500 mL) • Insulation • Bubble wrap • Glass fiber • Tesla coil • Copper wires
EXPERIMENT APPARATUS Rubber Stopper Nalgene Bottle (500mL) Methanol and Drierite Tesla Coil
MEASUREMENT APPARATUS • 120 f.p.s camera (Sony HDR-SR11) • Meter stick • Thermometer • Laptop • Temperature probe • Vernier Software: Logger Pro 3.8.4
KINETIC ENERGY • E = 1/2mv2 • Mass of cork (w/ line) before reaction • Film: observe frame-by-frame to find initial velocity
KINETIC ENERGY Frame 987 Frame 988
HEAT ENERGY q = mCp∆T
RESULTS • Total energy: kinetic energy & heat energy • Cork • Air in bottle • Bottle • Heat energy represented the majority of total energy • Equations in appendix were imported into Excel to make the spreadsheet
DATA ANALYSIS • Experimental ∆Hf of methanol: -535kJ/mol • Theoretical ∆Hfof methanol: -238.4kJ/mol • 124% error • Small ∆Hcresults in large experimental ∆Hf • ΔHc = [ΔHf (CO) + 2ΔHf (H20)] – [ΔHf (CH3OH)]
ADDRESSED PROBLEMS • Assumption that total energy transferred to cork • Bottle warm to the touch after reaction • Insulation to reduce heat loss to environment • Limiting reagent of reaction • Volume of methanol used (0.4 mL)
CONCLUSION • Energy not accounted for • Energy escaped from bottle • Multiple revisions to the procedure • In the future…
WORKS CITED • Slide 3 – Fireworks. http://www.wallpaperdev.com/stock/fireworks-wallpapers-fireworks-bang-pics.jpg(accessed May 8, 2013). • Slide 3 – Car Engine. http://www.yieldinsider.com/wp-content/uploads/2012/09/Car-Engine-1.jpg (accessed May 8, 2013). • Slide 5 – Exothermic and Endothermic Reactions. http://chemistry.tutorvista.com/organic-chemistry/hammond-postulate.html(accessed May 8, 2013). • Slide 7 – Methanol Structure. http://upload.wikimedia.org/wikipedia/commons/d/d1/Methanol_flat_structure.png (accessed May 8, 2013). • Slide 7 – Methanol Ball-and-Stick Model. http://upload.wikimedia.org/wikipedia/commons/d/db/Methanol-3D-balls.png (accessed May 8, 2013).