The Group

Reaction Chemistry  Initial reaction used: 6HCl(aq) + 2Al(s)  2AlCl 3 (aq) + 3H 2 (g)  Final reaction used: HCl(aq) + NaHCO 3(s)  CO 2 (g) + H 2 O(l) + NaCl(aq)

Calculations  12ml HCl = mol HCl = mol NaHCO 2  mol NaHCO 2 = g NaHCO 2  Pressure calculated = atm  13ml HCl = mol HCl = mol NaHCO 2  mol NaHCO 2 = g NaHCO 2  Pressure calculated = atm

Car Design

Testing Results Trial Number HCl (ml)Water (ml) Baking Soda (g) Feet traveled Modi- fications for next trial Small wheels Wait to open valve none New calculations Wheels attached to axel, new tape on nozzle of bottle none -No spew all runs

Performance Results (Wednesday, December 2, 2009) Trial Number HCl (ml)Water (ml) Baking Soda (g) Distance traveled Spew ’10”No ’5”No ’0” Some due to hand fault ’0”No

Performance Results (Wednesday, December 2, 2009) 25 feet exactly

Performance Results (Friday, December 4, 2009) Trial Number HCl (ml)Water (ml) Baking Soda (g) Distance traveled ’7” ’5” ’ No spew all trials We assume our bottle was starting to wear and could not hold the pressure which we needed to propel our car forward. We tried different caps, but were still losing some pressure before every run.

Conclusion  Our car had a very simple design that allowed us to attach the bottle to the car quickly and smoothly.  The car rolled well, but we still could have tried to find a way to make the friction of the axel less which would have allowed the car to roll even smoother.  Near the end of the competition our bottle started to leak gas, lessening the pressure. We should have gotten a new bottle and cap to use to ensure that no pressure was lost.  Our car performed better than we expected by reviewing the results in our trial runs. We were very pleased with its performance and making it to the finals.