A Chemist Celebrates the International Year of Light
Happy New Year! Did you know that 2015 is the International Year of Light (IYL)? IYL is a “global initiative adopted by the United Nations to raise awareness of how optical technologies promote sustainable development and provide solutions to worldwide challenges in energy, education, agriculture, communications and health1”. IYL is sponsored by several organizations with interests in science and science education, including the European Physical Society, the Institute of Physics, the American Physical Society, and the American Institute of Physics. You can find several lesson plans, videos and other educational resources on the IYL website2.
Solution to Chemical Riddle #1
In the video below, you can find the solution to the chemical riddle involving the food dye and bleach experiment.
Can you solve this chemical riddle?
Can you solve the chemical riddle described in the video below?
Flipping Pennies and Burning Candles: Adventures in Kinetics
In this Activity, students collect data to determine whether two processes, flipping pennies and burning small birthday candles, follow zeroth- or first-order rate laws. Students first collect data on the number of pennies remaining "heads up" after several successive tosses and then measure the mass of a burning candle over time.
Out of the Blue
In this Activity, students first prepare a standard formulation for a variation on the classic blue bottle reaction using consumer chemicals. They then make appropriate changes to the formulation and observe the results to determine the roles played by each reactant. This Activity could be used with units on chemical kinetics and oxidation-reduction reactions.
Determining Rate of Flow through a Funnel
In this Activity, students make funnels using plastic beverage bottles and rubber stoppers with differing numbers of holes or sizes of holes. They then determine the rate of flow of water through the funnels and identify factors that affect the rate of flow. This Activity uses easy-to-observe phenomena that model a chemical reaction with an identifiable rate-controlling step.
Cool! Rates of Heating and Cooling
In this Activity, students measure the rate of warming for a chilled thermometer bulb held in room temperature air, for a chilled bulb held between two fingers, and for a few milliliters of ice-cold water. Students discover that the warming process is not linear. This Activity emphasizes the importance of measuring temperature change and its relevance to other experiments.
Where There's Fire There's...
In this Activity, students compare the combustion of different substances such as a glowing wooden toothpick and lit birthday candle in air, oxygen, exhaled breath, and carbon dioxide environments. The oxygen and carbon dioxide are generated from supermarket chemicals. This Activity can be used to explore the chemistry of oxygen and combustion.
The Effects of Temperature on Lightsticks
In this Activity, students observe and compare the behavior of three lightsticks that are exposed to three different temperature ranges (cold, room temperature, and hot). The Activity could be used early in the school year to give students practice in making detailed observations and devising reasonable explanations for those observations. It illustrates the use of qualitative vs.
Putting UV-Sensitive Beads to the Test
In this Activity, students observe UV-sensitive beads that have been melted into flat disks, explore the temperature behavior of the disks, and then use the disks to investigate the effectiveness of different sunscreens. The Activity shows applications of chemistry in the real world.