"A bear is wiser than a man because a man does not know how to live all winter without eating anything." Abenaki (People of the Dawn) saying. This is the third post describing the metabolic and nutritional chemistry of bear hibernation.
Millions of years of evolution has endowed brown (Ursus arctos) and black (Ursus americanus) bears with the enviable metabolic capacity to starve themselves for a long period of time and still survive. Truly, bears are chemist extraordinaires and their hibernation chemistry overall is arguably without equal in the mammalian world. Let's take an introductory look at what's going on.
I just finished my first week of school, like many teachers in the Midwest. I work hard to get my Honors Chemistry students in a lab setting as soon as possible. It is difficult to find a perfect lab to do on the first or second day of school. In my mind, the ideal first chemistry lab would require no prior chemistry knowledge, involve interesting chemistry, address an NGSS standard, be relatively safe, not require expensive glassware or lab tools, and reinforce positive class norms. I have found engineering labs fit the bill! I don't know if I have found the "perfect" lab, but I have found something close I want to share!
Organic Chemistry is overlooked as a first year chemistry topic in most areas, but it can be a very valuable and fun experience for students. This is an activity that can be used to introduce students to functional groups.
Erica Jacobsen shares highlights from the April 2019 issue of the Journal of Chemical Education.
I came across an interesting Journal of Chemical Education article that explains how it is possible to crosslink sodium alginate, leading to the formation of calcium alginate beads. Calcium alginate beads are hydrogels and one of their uses is to immobilize enzymes in their structure. I thought it would be cool to immobilize some lactase enzyme onto calcium alginate beads and investigate its ability to hydrolyze lactose.
I’ve always been fascinated by advanced polymeric materials; it’s amazing how materials that are generally considered “plastics” have such stunning properties. I recently watched a couple of movies about Batman and it came out that some of his devices and protections are made of advanced polymers. In particular, the suit is almost entirely made of Kevlar.
The recently published iPad app ChemTube3D (and related website for classrooms without iPads) will be discussed. It has a great deal of functionality - including a large selection of organic mechanism animations and models of structure and bonding.
My first year teaching chemistry, I was looking for a soap-making lab or activity that I could run in my chemistry class with 25-30 students working at the same time. I usually do this activity right before spring break, as it provides enough time for the soap to harden and cure (high school students are impatient to use their soaps right away, which you should not do with cold process soap). I have used the activity at different points in the curriculum: during intermolecular forces during acids and bases, and during stoichiometry. Although I know teachers who use soap making as a project during their stoichiometry unit, I chose to not emphasize the calculations as it would require more time than I have available. Simply making the soap easily fits in a 45-minute period.
For a recent unit on organic chemistry for my IB students, I tried something new. I gave them a handout with a list of organic compounds (by class/functional group) and a list of mechanisms and reaction types. Their task (in small groups), using either butcher paper or a large whiteboard, was to create a flow chart of reaction pathways.