We will be doing Lab 8 – Thin Layer Chromatography for lab tomorrow. Lab6/7 are being redesigned and parts will be used for a handout next week that will be assigned for practice.
The grades for CEM131 are posted for Post Exam 2. There was a formatting error in the one I showed the morning class which had some grades screwed up. I have corrected the error, but please double check against your handed back work.
Wow, looks like a good chunk of people read the exam from last term in CEM131 and used that as study. Here is some advice, I change a significant chunk of questions between terms… And I knew, due to a question a student asked, that the old test was being used… So I made sure a changed almost every question.
Yes we have a quiz on Wednesday. Since it is on a new unit I would think vocabulary is important.
Here are the Syllabuses for the CEM131 Sections. The only change is the loss of Week 3 lab with the shift of the other labs down one week (eliminating lab 5) due to Convocation. Since Convocation (the change) is on Tuesday and your class is M/W, it does not affect lecture/exam schedule.
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).
REFUND/DROP NO W BY: 9/14/2017
DROP WITH W BY: 9/15/2017
WITHDRAW LAST DAY BY: 12/11/2017
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.
Here are the grades for CEM131, we will go over them in class.
Here is a copy of the questions from class with the last four answered.
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.
Here are the solutions for most of the questions in the practice set… I gotta have some fun with the remaining two.