Wednesday, November 16, 2011
3 Demonstrations by Miss Leland
Our teacher, Miss Leland performed three demonstrations. One with Ethanol, another with Hydrochloric Acid and Zinc, and the last with baking soda/vinegar. To begin with, she put Ethanol into a soda bottle and swirled it around. It was transforming into a gas. When heat (energy) was added it was supposed to launch forwards, but instead it just stayed lit for a few seconds and went out. Next, she combined baking soda and vinegar. The baking soda and vinegar combined int oCarbon Dioxide. After they were mixed together, she lit two candles. She poured the gas over the candles and they both suddenly went out. This is because fire needs oxygen to continue burning. So, when we poured the Carbon Dioxide over it, it went out because Carbon Dioxide is the opposite of Oxygen. Since the fire was surrounded by CO2 (Carbon Dioxide), it didn't have the Oxygen required for it to maintain the chemical reaction required for the flame to stay consistent. Finally, we did the test with Hydrochloric Acid (HCl) and Zinc (Zn). We created ZnCl2 + H2. We also applied heat part of the way through it. Heat or energy can at times be a catalyst that is needed to start or speed up the chemical reaction. Once the Zinc was introduced, it bubbled and released steam (gas). The gas was Hydrogen. We then added fire and it sped up the process. The Zinc was broken into small pieces by the end of the reaction.