Every LED light has a "band gap". Electrons are pushed into an empty orbital which is negative and then the positive end of the circuit attracts the electrons. As they go down in energy through the band gap, they emit light. The larger the band gap, the more energy, the smaller the wavelength and the closer to the "blue" end of the spectrum. So, the key is to try to control the band gap and thus control the color of light.
inquiry-based discovery learning
Food chemistry is an interesting and fun class for students. Read the article for some suggestions about resources along with an outline of a unit developed around water in cooking.
Fostering Creativity in Chemistry
The February 2017 online issue of the Journal of Chemical Education is now available to subscribers. Topics featured include: surface chemistry; chemical identity thinking; conceptual understanding; communicating science to the general public; activities and labs linking chemistry and art; history and chemistry; early access to research; technology as instructional support; synthesis laboratories; from the archives: bottle chemistry.
The chemistry of the Sky Blue dye found in McCormick's Color From Nature food colors is explored. This is part one of a three-part series in which the chemistry of McCormick's Color From Nature food colors is presented.
Ringing in Volume 94
The January 2017 issue of the Journal of Chemical Education is now available online to subscribers. Topics featured in this issue include: NMR spectroscopy; examining assessment; inquiry-based practices; cost-effective instrumentation; miscibility demonstrations; innovative laboratory experiments; from the archives: lightsticks.
You probably know what happens when you place dry ice in water. Do you know what happens when dry ice is placed in acetone or glycerin? Read this and find out!
Improving Student Understanding
The December 2016 issue of the Journal of Chemical Education is now available online to subscribers. Topics featured in this issue include: synthesis in the laboratory, examining and using a flipped classroom, improving labs through multimedia-based and student-directed learning, using applied math for better understanding, improving student understanding of thermodynamics, inclusive chemistry teaching, using manuscript review for assessment, climate chemistry, spectroscopy experiments, performing safe demonstrations.
Have you ever wondered where the cloud comes from when dry ice is placed in water? If you think the answer is “atmospheric water vapor”, be sure to read this post because experimental evidence suggests that this explanation is wrong.
Students are told that they have to determine the amount of active ingredient in an antacid tablet. Then I ask them if they have any questions. First it starts with blank stares...then slowly the questions start coming. What exactly is the active ingredient? What does it react with? They are provided information that the active ingredient is baking soda.
Teachers are accustomed to implementing new learning standards developed by state or national leaders. My state, Georgia, chose not to adopt the newest national standards. State leaders wrote the “Georgia Standards of Excellence” instead. Full implementation of the GSE begins in the 2017-2018 school year.