Have you seen the "salting-out effect"? This interesting demonstration shows a separation of two layers in a solution of water and an organic solvent by adding an ionic salt. Although this concept has important applications in organic chemistry and biochemistry, it can also be visually stunning and engaging for audiences. Read on to learn how to incorporate this demonstration into your chemistry lessons.
Nora Walsh outlines the interactive notebook pages she uses for her unit on REACTIONS. All of the documents and foldables are available for download.
Solutions are all around us in life and chemistry class! On February 10th, 2022, Kristen Vanderveen discussed solubility curves, molarity calculations, using particulate level modeling and simulations, making real world connections and so much more in this ChemBasics Talk. View a recording of her presentation and access materials she has suggested here.
The unspoken word of chemistry: Non-stoichiometric. Stoichiometry and non-stoichiometry are concepts that combine to make a solution that does not have to be difficult to understand.
Thermal paper such as that used for point of sale receipts typically functions by darkening when exposed to heat. The pigment system used in this paper also darkens when exposed to solvents of intermediate polarity and acids. This enables thermal paper to be used as an inexpensive sort of indicator paper for a variety of demonstrations.
The differing electrostatic and solubility properties of starch and polystyrene foam packing peanuts are used in various demonstrations to describe aspects of microplastics and their interactions with the environment. Their differing responses to exposure to liquid nitrogen and iodine solutions are also described.
Have you seen the rainbow candy experiment? It's a very simple experiment that involves pouring water into a plate that has M&M's candies or Skittles arranged in a pattern. Very curious shapes of sharply divided regions form spontaneously. How does this happen?!
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.
Ever wonder why some call precipitation reactions "double decomposition". Perhaps (or perhaps not) two (double) salts are sort of splitting apart (decomposing?) and then reforming with other radicals. But a solvent (usually water) is necessary to achieve the desired effect. But is adding water to a salt really decomposition?
The solution to "Chemical Mystery #16: A Red, White, and Blue Chemistry Trick for You!" is presented. How this experiment can be used as a springboard to carry out a simple quantitative analysis of salt solubility is also discussed.