Density Bottles can be used to teach a variety of chemical concepts such as density, solubility, and polarity. In this post it is shown that Density Bottles can also be used to differentiate between heterogeneous and homogeneous mixtures, and to explore light scattering.
As we all know, research and general educational practice clearly indicates that students learn science best by doing it – not just reading about it. Hands-on, process and inquiry based science is the key to understanding science. Unfortunately, this is a double edged sword for science teachers in that doing science has its potential hazards and resulting risks. Science laboratories, classrooms and field work sites can be unsafe places to teach and learn. If a student gets hurt while doing an activity in the lab, in the field or even at home if it was a teacher’s assignment, there is potential shared liability for both the teacher and the school.
I recently watched a video in which a chemist (who goes by the nickname “NurdRage”) activated a chemiluminescent reaction by vapor deposition. I wanted to try it out for myself! Unfortunately, oxalyl chloride is toxic, corrosive, and a lachrymator. Thus, the experiment conducted by NurdRage needs to be conducted in a hood, and it is not particularly amenable to simple presentations. I began to wonder how I could create this vapor activated chemiluminescence using simple materials.
Over the past 30 years, numerous articles have been written about the importance of student teacher relationships. The National Education Association, NEA, offers advice for beginning teachers that includes establishing the classroom climate, conducting class efficiently, and reaching all students. When teachers effectively connect to their students, discipline problems decrease and student engagement increases.
This post was submitted for the 2017 ChemEd X Call for Contributions: Creating a Classroom Culture.
In Chemical Mystery #10, plastic straws are observed to “magically” change color when waved in the air. Check out the explanation and the video.
In this simple trick, colors are made to "magically" appear and disappear on a straw. This science experiment is very easy to do...if you know your chemistry!
I saw the process of students thinking like scientists but what I struggled with, and I imagine many others do as well, is how students work together in groups. Yes...I know it is important but is this a big battle that I want to fight? I was fortunate to meet several people who have developed some wonderful “tricks of the trade” to help students work as “teams”.
If rhubarb stem is placed in a solution of permanganate, the purple permanganate ion is reduced to the colorless Mn2+ ion. It is thought that the oxalic acid present in rhubarb causes this reduction. The investigations presented in this post provide evidence that this may not be the whole story...
I think this experiment provides a fantastic vehicle to involve students of all ages in small, hands-on and exploratory research projects. Like many others, my students and I have investigated various aspects of this interesting fountain.
Are you familiar with the dynamic density bottle experiment? This interesting experiment was invented by Lynn Higgins, and is sold by various science supply companies. Two immiscible liquids (usually salt water and isopropyl alcohol) and two different types of plastic pieces are contained within a dynamic density bottle. The plastic pieces display curious floating and sinking behavior when the bottle is shaken.
