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Flinn Lab Activities and Demonstrations
1-800-452-1261
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General, Organic and Biological Chemistry Kits,
continued
Ruby-Red Colloidal Gold—Laboratory Kit
By: The Flinn Staff
From nanotech fibers and nanosensors to nanobots, nanotechnology has created so much “buzz” that it is hard to tell where the science ends and the science fiction begins. Wherever it may lead in the future, the science of nanotechnology begins with solid particles called nanopar- ticles that are 1–100 nm in size. Shrinking the size of solid-phase particles to the nanometer scale—one billionth of a meter—changes their physical and chemical properties. The surprising properties of “colloidal gold” are a good example of this phenomenon. Whereas normal or “bulk” gold is a bright, shiny, metallic yellow, colloidal gold nanoparticles are red or blue, and not at all shiny.
Students prepare a sample of gold nanoparticles and qualitatively investigate the scattering of light by the particles with a laser pointer. Then they use a spectrophotometer to construct an absorbance spec- trum. The effect of particle size on the color of the nanoparticles is also investigated.
Complete for 24 students working in pairs. Laser pointers are required and available separately.
Iodine Clock Challenge—Laboratory Kit
By: The Flinn Staff
The demonstration of an “iodine clock” involves a chemical reaction that suddenly turns blue due to the formation of the familiar iodine– starch complex. The color change occurs abruptly, like an alarm clock ringing. Can students predict the amount of time it will take for the iodine clock to ring? This guided-inquiry activity allows students the opportunity to observe the iodine clock reaction, analyze how the concentration of potassium iodate influences the rate of the reaction, and then predict the amount of potassium iodate needed to make the clock “ring” in 25 seconds and verify the accuracy of their prediction.
Complete for 24 students working in pairs.
Exploring Equilibrium—Laboratory Kit
By: The Flinn Staff
The word equilibrium has two Latin roots: aequi, meaning equal, and libra, meaning weight or balance. Our physical sense of equilibrium—in the motion of a seesaw or the swing of a pendulum—suggests an equal balance of opposing forces. How does this physical sense of equilibrium translate to chemical equilibrium?
In this activity, students explore the nature of chemical equilibrium of two different reversible reactions. First, they study the formation of a complex ion and investigate the effects of changing the concentrations of reactants and the reaction temperature. Students then study acid–base equilibrium by observing the color changes of an indicator. Students practice critical-thinking skills as they build on their observations and apply their knowledge to predict whether a reaction is exothermic or endothermic, based on the effect of temperature on the position of equilibrium.
Complete for 24 students working in pairs.
Ruby-Red Colloidal Gold—Laboratory Kit AP8026
Catalog No.
Description
Price/Each
AP8026
Ruby-Red Colloidal Gold—Laboratory Kit
$74.70
AP8934
Laser Pointer
25.50
Iodine Clock Challenge—Laboratory Kit AP8027
General, Organic and Biological Chemistry—36 Kit Bundle
Save by ordering the complete General, Organic and Biological Chemistry 36-kit bundle! Comprehensive, cost- saving bundle includes all 36 kits on pages 4–14 and the
372-page GOB lab manual.
Catalog No.
Description
Price/Each
AP8044
General, Organic and Biological Chemistry—36-Kit Bundle
$2410.00
Catalog No.
Description
Price/Each
AP8027
Iodine Clock Challenge—Laboratory Kit
$53.55
Catalog No.
Description
Price/Each
AP8028
Exploring Equilibrium—Laboratory Kit
$27.70
GENERAL, ORGANIC AND BIOLOGICAL CHEMISTRY continued on next page.
Exploring Equilibrium—Laboratory Kit AP8028