So, you want to do a “Magic Show!” Student Presenter Packet for y-chem Outreach Program (10/11/2014)
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- Disposal After the ashes and charred remains have cooled down (be sure of this), dispose of them in the trash. Chemistry
- Collapsing Can Demonstration
- Disposal Empty water from can into drain. Dump the ice down the sink. Chemistry
- Clean Up Ensure that all the ethanol has dried/burned before transporting the tornado. No cleanup is required. Chemistry
- Nylon Rope Demonstration
- Disposal Place the solutions in the appropriate “nylon rope” waste. Misc. notes/Performance
Gun Cotton (Nitrocellulose)Cotton is soaked in an acid solution to form nitrocellulose, which completely combusts in a smokeless flame. SafetyWhen preparing gun cotton, do all steps in the hood. Toxic gases may evolve. Use caution when working with concentrated acid solutions, they are extremely corrosive. Never ignite the Gun Cotton in your hand. DisposalAfter the ashes and charred remains have cooled down (be sure of this), dispose of them in the trash. ChemistryGun cotton is nitrocellulose C6H7N3O11 cotton. Cotton balls, which is 90% cellulose C6H7O5, are placed in fuming nitric acid. The hydroxyl groups on the cellulose are replaces with nitro groups. 
When lit, the cotton goes up into a ball of smokeless flame from complete combustion. PresentationBurn cotton on the ceramic tile, then, using tongs, grab some gun Cotton and set it on the remaining smoldering cotton. It should go up in a flame immediately. Collapsing Can DemonstrationThis demonstrates atmospheric pressure by creating a partial vacuum in a can, causing external atmospheric pressure to crush it. Set UpFill the can with about an inch of water and then set it on top of the hot plate with the hot plate on high (l0). It will take at least 10 minutes for the water to be heated enough to where it is readily streaming out of the can. Have the ice tray nearby. SafetyBoiling water can cause burns, so use the orange heat gloves to hold the can. DO NOT ALLOW THE HOT GLOVES TO GET WET, OR THEY WILL CEASE TO INSULATE! DisposalEmpty water from can into drain. Dump the ice down the sink. ChemistryWater vapor replaces the air in the can as it is heated. When the can is sealed and cooled, the vapor condenses, creating a low-pressure system on the inside of the can. The relatively high pressure outside the can causes it to be crushed. PresentationDo not attempt until steam is visibly coming out of the top of the can and has boiled for a few minutes to push the air out and allow the water vapor to fill the can, but do not let it boil to dryness Wearing gloves, take the can off the hot plate and tightly stopper the can. Put the can in the ice, and roll it to get the best results. The can will implode quickly. Watch your fingers! DO NOT THE WALLS OF THE CAN- ONLY HANDLE LID AND BASE- OTHERWISE YOUR FINGERS WILL BE PINCHED WHEN THE CAN COLLAPSES. Flaming TornadoBurning alcohol in a beaker surrounded by a mesh wire column, a vortex of fire is generated. Using inorganic salts the color of the vortex can be changed. Set UpBring out all equipment. Place crystallization dish inside the metal beaker in the middle of the turntable. Pour about 300 mL ethanol into beaker. Add a small amount of an inorganic salt (or a combination). Some choices include CuCl2 (green), KMnO4 (purple), LiF (magenta), NaCl (yellow) and SrCl2 (red). Place mesh cover next to apparatus. SafetyBe very careful with the apparatus after you start the flame – the metal can get very hot. If the apparatus runs for long enough the glass may break. If this occurs clean up the pieces carefully. Clean UpEnsure that all the ethanol has dried/burned before transporting the tornado. No cleanup is required. ChemistryWhen atoms are exposed to heat, their electrons are excited and promoted to a higher energy level. As they return to their lowest-energy state, they emit the extra energy as photons (light packets). Each salt’s unique color corresponds to its elements’ own differences in energy levels. PresentationUse the lighter to ignite the ethanol. Place the aluminum mesh over the apparatus, sliding it into the sheath. Turn out the lights and turn the handle of the apparatus. The ethanol initially burns yellow. The flame will change colors as the salt(s) diffuse. Abruptly stopping the turntable and then turning it the other direction often shows a color change. To extinguish the flames, remove the mesh with caution as it may be hot, and cover the beaker with the pie dish. Elephant’s ToothpasteA small amount of KI is put into a solution of hydrogen peroxide and dish soap, and yellowish-white foam shoots out of the graduated cylinder. SafetyThis demo is exothermic and the foam created has 30% hydrogen peroxide in it. Do not touch it or allow anyone else to do so. Also be careful when setting up and demonstrating not to use too much solution, because it will overflow the plastic tray and make a mess. DisposalWait until students are gone, and (using the provided gloves) wash this demonstration out in a large sink (ask if there’s a janitor’s closet you can use) Wash everything in the sink; all the chemicals can be disposed of that way. ChemistryThis reaction demonstrates the decomposition of hydrogen peroxide (H2O2) with a potassium iodide catalyst. It is a two-step reaction: H2O2 (aq) + I – (aq) → H2O (l) + OI – (aq) (rate determining step) H2O2 (aq) + OI – (aq) → H2O (l) + O2 (g) + I- (aq) The brown, yellow color of the foam indicates the presence of iodine in solution as the I3-(aq) species as a possible side reaction. The dish soap just acts to collect the oxygen gas as it is evolved. PresentationMake some comments about having elephants and needing toothpaste and then dump the KI into the graduated cylinder. Nylon Rope DemonstrationA nylon thread is formed when two immiscible liquids are mixed. The nylon rope can be pulled to extensive lengths using forceps or wound on a windlass (crank). For demonstrationGather two 1 liter stock bottles, one labeled “Nylon Rope Top Solution”, and the other labeled “Nylon Rope Bottom Solution”. Also, set out the windlass on a stand. SafetyAll these reagents are very toxic and cause nausea. Make sure you prepare all of these solutions in the hood and wear protective eyewear and gloves. ChemistryNylon, or synthetic polyamides, are formed from diamines and dibasic acids and are designated by one number for each. In this demonstration we form 6-10 nylon with hexamethylenediamine and sebacic acid, although the sebacic acid is represented by sebacoyl chloride in the reaction shown: H2N(CH2)6NH2 + ClCO(CH2)8COCl [HN(CH2)6HN-CO(CH2)8CO] + 2 HCl This type of reaction is called interfacial polycondensation. It is especially useful because it is a low temperature process, and will react rapidly at room temperature. Another beneficial component of this reaction is that it does not require exact stoichiometric ratios. Nylon 6-6, a commercially used polyamide, can be made by substituting adipoyl chloride for sebacoyl chloride. H2N(CH2)6NH2 + ClCO(CH2)4COCl [HN(CH2)6HN-CO(CH2)4CO] + 2 HCl PresentationPour some of the bottom solution into the beaker, then pour an equal amount of the top solution onto the bottom solution. With the tweezers, grab the interface between the two liquids and pull it up and above the beaker. Begin to twist the tweezers to show the continuous thread of nylon formed or use the windlass provided to wind it. To show the interface better, use food coloring or phenolphthalein in the bottom solution. DisposalPlace the solutions in the appropriate “nylon rope” waste. Misc. notes/PerformanceThe nylon rope can be stretched to great lengths. To emphasize this, you can put the beaker on the floor, stand up on the desk, and use the forceps to pull the nylon as high as your arms can reach. The string can then be wound around a windlass to further demonstrate the length. Page | Directory: wp-content -> uploads -> 2014 2014 -> For want of a nail 2014 -> Stop Militarizing Law Enforcement Act of 2014 2014 -> Ihbb asian Championships 2014 middle school bowl Round 4 First Quarter 2014 -> Ihbb european Championships 2014 Bowl Round 4 First Quarter 2014 -> International History Bee and Bowl 2013-14 Asian Division Question Set Bowl Round Six 2014 -> United states patent and trademark office 2014 -> Coffs harbour eisteddfod vocal syllabus 2014 -> Listen News Programs Schedule pledge now 2014 -> Slow club announce third album complete surrender Download 177.95 Kb. Share with your friends:
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