The Devil's Milkshake
The Devil's Milkshake is a simple, yet interesting chemistry experiment that fits well as a Halloween demo.
The Devil's Milkshake is a simple, yet interesting chemistry experiment that fits well as a Halloween demo.
Biosorption is a method that can be used for the removal of pollutants from wastewater, especially those that are not easily biodegradable. This experiment uses citrus fruit peels as part of a iodometric titration to conduct a wastewater treatment binding copper.
A few years ago, the faculty in our department at Slippery Rock University of Pennsylvania decided to switch to an atoms first approach to the General Chemistry course. We took advantage of this change to systematically redesign the first semester of the laboratory curriculum to be a true “laboratory course” that focuses on laboratory practices, techniques, and equipment rather than on chemical theory.
It can be difficult to engage students in reviewing for semester exams by using worksheets or practicing problems on the whiteboard. If you are looking to change up your review plans, you might consider using a lab activity that provides opportunity to revisit many of the topics that need to be covered.
Looking to change up your titration lab? Citric acid is very common in candy and other foods. Students will be engaged in using titration to find the amount of the acid in Mentos Now or other candy. Student and teacher documents are provided to help you use the activity with your own students.
Titrating this year for me has an added complication. The complication is that half of the science department has to be completely packed up and out of our rooms, including chemicals and equipment, before school ends. Half of the department is going to be completely remodeled (my half of course). Teaching must still go on in the middle of the madness.
I tend to enjoy acid base titrations for several reasons. First, students get to work with burettes, acids, bases and they see a nice "color change" when they reach an endpoint. Many times, students who tend to struggle with pen and paper testing excel at the "hands-on" approach. Titrations also dovetail well with stoichiometry which provides a nice review of information closer to the end of the year.
This activity was submitted for a 2016 ChemEd X Call for Contributions soliciting input regarding the big ideas being put forth by organizations like AP. The author shares a lab activity that relies on connections - between stoichiometry, esterification, equilibrium, kinetics, titrations and uncertainty of calculations. He also shares the resources he created.
I recently stumbled across a blog about the use of BCA (Before Change After) tables for stoichiometry written by Lowell Thomson. I was thrilled to discover ChemEd Xchange! I wanted to share my journey, spurred on by my students, into the extensive use of the BCA approach in AP and