The Density Bottle is Red, the Density Bottle is Blue...
Tom Kuntzleman | Fri, 05/30/2025 - 10:10
You're going to love this new color variation on the Density Bottle experiment!
solutions
Exploring Color Separation in Salting-Out Experiments
Tom Kuntzleman | Sat, 05/04/2024 - 07:44
Adding dyes to salting out experiments can create a variety of interesting color effects as the dyes differentially dissolve in the aqueous and organic layers. Can this differential solubility of dyes be explained using intermolecular forces as a guide?
A Demo A Day III: Demonstrations and Props Used in My General Chemistry II Classes
Dean Campbell | Sun, 05/21/2023 - 10:50
Dean Campbell tries to use at least one demo for every class to illustrate concepts described in his chemistry courses. In this post, he includes short descriptions of the demonstrations and props he has used while teaching his collegiate General Chemistry II courses.
Solution to Chemical Mystery #19: Multi-colored Mixture
Tom Kuntzleman | Sun, 02/06/2022 - 13:22
Did you figure out how to create a multi-colored mixture? Check out the solution to Chemical Mystery #19: Multi-colored Mixture!
Freezing Point Depression Near Body Temperature with Eicosane and Azobenzene
Dean Campbell | Tue, 11/02/2021 - 11:20
Addition of a small amount of azobenzene to eicosane can lower its melting point to where it can be melted by body heat. This can be used in demonstrations and classroom activities related to freezing point depression and phase diagrams.
Demonstration: Colorful Sugar Density Column
Nick Thomas | Tue, 03/23/2021 - 09:52
Assembling a large graduated cylinder with colored sugar solutions of various densities is described. By filling the cylinder in the reverse order from bottom up, very little mixing occurs resulting in an attractive classroom demonstration to illustrate density. Students also have to opportunity to practice density and dilution calculations.
Developing a Model for Enthalpy of Solution—Reframing the Approach
Ben Meacham | Wed, 03/17/2021 - 10:30
Ben Meacham decided to alter his approach to teaching about enthalpy and focus on getting students to first develop the mathematical model for enthalpy of solution so they could eventually apply it to make predictions for different solutes being dissolved. In this blog post he shares the process he used with his class.
Solubility and Concentration - A Free Virtual Chemistry Lab Activity
Josh Kenney | Fri, 11/13/2020 - 14:46
In this activity, students learn about solubility and concentration. They watch videos that explain the dissolving process, how to calculate the molarity, supersaturation and how to make rock candy. They also use a PhET simulation to explore factors that affect the concentration of a solution.
Argument Driven Inquiry and Heat of Solutions
Chad Husting | Fri, 04/20/2018 - 20:08
I have blogged about Argument Driven Inquiry (ADI) previously. It has been a popular topic on ChemEd X lately. During my limited experience, I have found the process to be a bit drawn out but extremely helpful and beneficial. The time spent has been well worth it.
The Density Bottle Strikes Again
Tom Kuntzleman | Fri, 12/01/2017 - 07:48
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.