By Logan Olsen, Chase Huntley, Chuck Corbett

HCl (aq) + NaHCO 3 (aq) → NaCl (aq) + H 2 O(l) + CO 2 (g)  We tried HCl and baking soda at first, but after many inconsistent trials we switched to Vinegar and baking soda. Pv=nRT R= L*atm/mol*K T=293 K (room temp.) V=0.7 L (volume of propel bottle) _____(2.5 atm)(0.7 L)______ = mol CO 2 (g) ( L*atm/mol*K )(293 K) mol CO 2 (g)1 mol NaHCO 3 84 g NaHCO 3 1 mol CO 2 1 mol NaHCO 3 = g of baking soda L0.073 mol HCl 12.1 mol = L HCl All of the mole ratios are one to one. To find the amount of liters needed of HCl we used the molarity of HCl and canceled the moles out. In our experiment we multiplied all of the values by two because we increased our pressure to 5.0 atm.

CH 3 COOH (aq) + H 2 O(l) + NaHCO 3 (aq) → H 2 O(l) + CO 2 (g) + NaCH 3 COO(aq) The vinegar had five percent acidic acid- 5% (AA) Pv=nRT R= L*atm/mol*K T=293 K (room temp.) V=0.7 L (volume of propel bottle) ______(5.0 atm)(0.7 L)______ = mol CO 2 (g) ( L*atm/mol*K )(293 K) mol CO 2 (g)1 mol NaHCO 3 84 g NaHCO 3 1 mol CO 2 1 mol NaHCO 3 = g baking soda mol AA 60 g AA1 Cm 3 AA100 mL Vin 1 mol AA1.05 g AA5 mL AA = mL Vinegar We made other calculations for various pressure values (4, 4.25, 4.5, and 4.75 atm). But after some trials we determined that having 5 atm was the correct amount to have for the car to travel a distance of 25 ft.

Car Design Design #1: Our first design was poorly designed. Although it was rather simple, it didn’t uphold the ability to sustain the thrust of the pressure released Design #2: Our second design was also unsuccessful. It also dealt with the same problems. Design #3: Our final design is shown in the pictures posted above. It worked well for the amounts of vinegar and baking soda. Although we didn’t win the finals, the size of our car would result in the destruction of any other car to itty bitty pieces!!! Our car also is known to attack professors who wear shorts everyday.

Semi Final Graph Results Reaction ∆ Run #1 ∆ Run #2 ∆ Run #3 ∆ Run #4 ∆ Run #5 ∆ Run #6 Distance Place Cum Total CumPla ce Comme nts Vinegar / BS 25 out -185 s -80 s -185 s 180 s -30 s51104Spew

Mr. Smooth!  If you click on the link below you will see a brief video clip of how nonchalant Dr. Skip moves out of the way to dodge this speeding car of fury.

Conclusions  Overall our car was consistent. In the semi- finals we took advantage of the fact that we had unlimited runs in a two hour time period. We ran at least ten trials in the semis and had two strong enough scores to propel us into the finals. Our car ranged from about 10 to 20 feet.  In the finals we didn’t do as well we wanted but we finished in the middle of the pack.  We tried to nail Dr. Skip but he was far to elusive for our car.  Opening the valve was the biggest source of error in our experiment.

Final Thoughts  We could have changed our design to be smaller and easier to get started by the force created by the chemical reaction.  We only tried two chemical reactions. There are many more safe chemical reactions that we didn’t try that could have been more effective and create less spew.  We created the most spew out of anyone so we should most definitely get extra credit.