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!
Erica Jacobsen shares highlights from the August 2019 issue of the Journal of Chemical Education of special interest to our ChemEd X community.
The solution to Chemical Mystery #15: The Leaky Cup is shown here.
Time for a new chemical mystery! Watch the video below and see if you can use your chemical knowledge to figure out how this experiment is done.
What happens if you cool a Scrub Daddy sponge in liquid nitrogen (or dry ice) and subsequently strike it with a hammer? Let's find out!
The science behind the incredibly popular Scrub Daddy sponge is investigated. Part of the appeal of the Scrub Daddy sponge is that it changes from soft to hard depending upon temperature. This allows a single sponge to be transformed into a hard scrubber or soft sponge, depending upon the temperature of water into which it is placed.
The authors of the recent Journal of Chemical Education article, PolymerDay: Outreach Experiments for High School Students, offer a collection of interactive polymer activities designed to be part of an all-day outreach event for high school students. For teachers that might use the activities on separate occasions and/or as part of their curriculum, the authors recommend an accessible resource to support that work.
This is an ACS Authors' Choice article and is open access to all.
In this Activity, students compare polystrene and cornstarch packing materials ("peanuts"). Both are made of polymers, but because of their composition, they behave very differently in various solvents. Students extrapolate how these differences in behavior relate to environmental effects, such as filling landfills with non-biodegradable materials.
In this Activity, students first prepare a gel using the superabsorbent polymer sodium polyacrylate (found in certain diapers) and water. The gel is split into piles and samples of different compounds are sprinkled on the piles. Students determine that ionic compounds break down the gel, while covalent compounds have no effect on the gel.
In this Activity, students dye fabric squares with two plant dyes: aqueous extracts of tea leaves and of marigold flowers. They investigate how the addition of iron to a dye bath affects the resulting color and fastness of the dyed fabrics and observe that the type of fabric affects the results. This Activity can accompany a discussion of the impressive array of chemicals produced by plants.