Week 4 Reflection

In chemistry class this week, we continued to review and calculate measurements of various objects. One of the many experiments we conducted involved calculating the volume of abstract objects, or in our case, candy. Each group started off by selecting a type of small candy, such as Starburst, Skittles, M & M's, and peanut M & M's. Then, we were to fill a graduated cylinder up to a designated amount for each trial, for a total of five trials. After weighing the mass of five candies of the same sort, each measurement was to be recorded and compared to previous results. We then dropped a candy piece into the graduated cylinder and recorded the new risen measurement. The difference in the original amount of water and the new risen amount was the calculated volume of that piece. This was then repeated for the next four candies in new, clean water for each. Afterwards, we took the mass for each and divided it by its volume in order to discover the density of each.

One of the other experiments we conducted consisted of the question, "How thick is aluminum foil?" In order to answer this challenge, we were required to work backwards when working with our equations. Mr. Abud had graciously given us the designated density for volume (2.7g/cm³) and we weighed the mass of the foil ourselves. From there, the only remaining part of the equation left to solve is the volume. Since the equation for volume is length x width x height, we were able to calculate the height of it by measuring the length and width of the foil. We were then able to take the calculated volume from the density x mass equation and set it equal to the length x width x height equation to further help us find the height of the aluminum foil.

Another experiment we accomplished in class this weak was calculating the density of a gas. We started off by filling up the trough with water until it was barely above the "bench". The bell jars were then taken and filled cmopletely with water before being set aside. Then, we filled the flask with 100mL of water and measured its total mass on the balance scale, along with an alka seltzer tablet. We then used the watch glass to seal the bell jars before putting them in the trough over the hole connected to the hose. Once everything was set up, we dropped the alka seltzer tablet into the water and quickly sealed it with the stopper located the opposing end of the hose. As the tablet fizzed in the water, it created a gas that went up through the tube and out through the hole in the trough. This caused the water to rush out of the bell jar, for the gas created was causing the water to displace itself. Once the water was running out of the one bell jar, we quickly slid the second jar over the hole and let the gas continue to rush out as the flask was gently shaken to ensure the alka seltzer was through fizzing. The next day, we discussed our results in class and came to the consensus that liquids were less dense than solids, but more dense than a gas. Possible reasons for this were maybe the difference in the number of particles or maybe the actual size of the particles.