What Scientific ideas or theories would help you explain why you are able to use the procedures to analyze the evidence?
For the Killer Cup of Coffee Lab, and the Ink is Still Wet Lab, The colorimeter helped us infer who the suspect was by using light to determine what the amount of absorbency was at 635 nm, 565 nm, 470 nm, and 430 nm. We were able to use the procedures because we, as humans can’t find the absorbency by just looking at it, we need the accuracy of technology to precisely find the absorbency. For the First Impressions Lab we needed to make the impressions for the teeth, because we wouldn’t be able to make an accurate guess by just looking at the bitten cheese, and the different sets of teeth. Therefore we needed the plates to make the impressions so we could compare and contrast the different teeth impressions, and infer which pair was the suspect’s set of teeth.
How has your approach to lab procedures changed from the first round of labs? Are you more or less confident in you results? Why?
Since the first round of labs I think that I have learned a lot of really good tips from doing various experiments. One that applied to all of the labs was reading instructions. I learned that it is always very important to read instructions so that when doing procedures during the lab, you don’t get confused or have a lot of questions. For example, during the Killer Cup of Coffee Lab, when you had to use the colorimeter and record data it was really important to read all of the directions first. My group didn’t read all of the directions at first, and later we found out doing the rest of the lab to be very difficult, because we didn’t know how to use the equipment properly and we had to ask for a lot of help! Later on when my partner and I had to do, The Ink is Still Wet Lab, it also involved a colorimeter. We knew we had to read the directions because otherwise we would be totally lost. Reading the directions ahead of time resulted in our Lab going fast and very smooth, with little questions asked along the way. Another tip I learned along the way was to work efficiently. For this set of labs I knew we had to work efficiently because some of the labs took longer than others. For instance when working on the First Impressions Lab it didn’t take as long because all we had to do was wait for the plaster to harden, (which took an hour) and all that was left was the teeth imprints. Since that lab didn’t take as long, we used that leftover time to make up for the longer labs. The Killer Cup of Coffee was a longer lab so we decided to finish up the questions after finishing the First Impressions Lab. I think I was more confident in my results because since we have been practicing being accurate, using different tools, using different techniques, and knowing what to look for, it was reassuring to know waht we were doing, and what to expect.
