It is that time of the year when we are all excited and ready to rack up the 4.0 grades, the start of term.
This year is a little bit different for me. Due to staff retirements and the new HLC (Higher Learning Commission) requirements for highly qualified faculty, I have shifted around my schedule a little. I will be teaching CEM131 (Introductory Chemistry), CEM241 (Organic Chemistry I), and BIO220 (Introductory Microbiology). This goes back to my graduate degree in Microbiology and specialization in Bioorganic Chemistry (chemists who take to many biology classes and realize bacteria are better at organic chemistry than me).
Below are the final grades for BIO161. There was not a curve due to the high median (in the eighties), but this is in line with course policy. Overall performance was good, and the cladograms didn’t make me cry.
Congrats and good luck, don’t forget the student evals. You won’t hurt my feelings, I’m sure ex-girlfriends have said much worse about me.
Here are the final grades for the CEM131 class. They class median was 50% (which is high for nationwide standards) and the class high was 77% (in the 95% percentile nationwide). So I gave a curve of 23% to the final exam. Overall class performance was very good.
Now to the second issue, my huge brain fart in class. I knew when I worked it out (which was about five minutes after the last person left) I would want to bang my head on the board for missing the obvious. The problem was that we were solving the wrong problem. The Dilution Equation (C1V1 = C2V2) works when you think about how you made each experiment, not comparing different experiments. So looking at the second experiment you did, where you made the bleach solution by mixing 5 ml of bleach with 5 ml of water. Instead of comparing this to experiment one, think about the dilution itself. C1 = 1.7X10(-4) M, and the V1 = 5 ml (the amount of bleach added), C2 = x, and V2 = 10 ml (the amount of bleach plus the water added). Solve for C2 = (C1 X V1)/V2 which gives you a concentration half the original. in the third experiment, change V1 to 2.0 ml and you get 1/5 the original concentration. I told you it was simple.
I apologize for the brain fart. Sometimes when you are so used to doing the idea in your head, you forget how to translate it into the math… and this was one of those time.