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Complete a conductometric titration using Go Direct® Conductivity Probe. Data is automatically graphed in Graphical Analysis 4, and students can use the analysis tools to determine the equivalence point.

Our chemistry team recently posted a free experiment to our website, “Absorbance and Fluorescence Characterization of Vitamin B2.” In the experiment, students explore the properties of riboflavin using a spectrometer and our free, recently updated Vernier Spectral Analysis®. Spectral Analysis v4.8, released in February 2019, now includes fluorescence support. You still get the user-friendly interface that walks students through the data-collection process to easily set up a full spectrum experiment, Beer’s Law experiment, kinetics experiment, or emissions; but now you will have these options for fluorescence data as well.

Doug Balmer, a chemistry teacher from Warwick High School in Lititz, Pennsylvania, designed a lab experiment for his students that investigates the absorption and emission of light using a spectrophotometer. The experiment, entitled “Light Lab: Studying Light and Electrons,” is divided into four parts: understanding how a spectrophotometer works, seeing the connection between wavelength and color, observing atomic line spectra, and looking at the absorption spectra of solutions.

For several semesters I have had my freshman chemistry students monitor our campus water feature on a weekly basis using most of the Water Quality Index measurements. The water feature is an artificial pond, roughly two hectares in area and a meter deep. It has two fountains, an amphitheater, and a picturesque bridge that is good for hanging probes into the water. The pond is lined with black rubber, leading to considerable solar heating.

Recent visitors to the Portland Art Museum were treated to a viewing of the work One Ball Total Equilibrium Tank by the internationally renowned artist Jeff Koons. As visitors admired the piece, they often wondered how the basketball was being suspended in the centre of the tank without wires or other visible means of suspension. Was it an optical illusion? A magic trick? No, it was simply the intersection of art and science—a study in equilibrium and buoyant force. With dense, highly saline water in the bottom half of the tank, and less dense distilled water on the top, a basketball of just the right density is held in place by opposing forces.

In an iodine redox titration, starch, which turns blue-black in the presence of iodine, is typically used as the indicator. However, this method can be challenging for students because of the low solubility of iodine in water and the pH dependence of the reaction (which proceeds quantitatively in neutral or slightly acidic solutions). Did you know that there are a couple of variations on this experiment that can create a more successful experience for your students?

Taking full advantage of the Vernier Mini GC Plus, Mr. William Patrick Cunningham, from Claudia Taylor Johnson High School in San Antonio, Texas, designed an innovative experiment in which students study intermolecular forces. The experiment uses different alcohols to demonstrate how variations in molecular structure and molecular mass affect the speed at which a molecule’s vapor passes through the chromatography column.

Many schools can’t afford a classroom set of spectrophotometers. So how can you use a single spectrophotometer and a class set of colorimeters to have your students discover the best wavelength of light to use in an experiment?

Are you interested in spectroscopy but don’t know where to begin? You are in luck! We’ve recently designed a new experiment, “A Guided Inquiry Approach to Understanding Fluorescence Spectroscopy,” to help students understand what goes on inside the “black box” of a spectrophotometer.

As part of the investigation of a crime scene, detectives note that a white powder is found at the location. Even though they have their suspicions, chemical and physical analyses must be performed to determine the identity of the powder. That’s where the crime scene technicians take over.