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Atomic Structure
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Atomic Structure—Demonstration Kits, continued
Is There Sodium in Bananas?
Flame Test Demonstration Kit
By: The Flinn Staff
Bananas are a good source of potassium—but do they also contain sodium? This flame test demonstration provides a safe method for observing excited-state emission colors of metal ions—no flammable solvents required! Procedure involves producing an aerosol of metal ions by reactions of carbonate salts with acid. Demonstrate the char- acteristic colors produced by three different metal ions, and then let students identify which ions are present in bananas. By the way, the answer to the question is yes—in more ways than one! Demonstration Notes, reproducible student worksheets, and enough materials to perform both parts of the demonstration seven times are included. Concepts: Properties of metals, atomic structure, emission spectra, nutrients in food.
Time Required: 20 minutes
Materials Provided: Banana chips, calcium carbonate, potassium carbonate, sodium carbonate, vinegar, weighing dishes.
Note: Three borosilicate glass Petri dishes are required.
See free video at flinnsci.com.
Kaleidoscoptical Activity—
Demonstration Kit
By: Bob Becker, Kirkwood H.S., Kirkwood, MO
A radially polarized filter is placed on an overhead projector stage and a regular (parallel) polarized filter is positioned above it. As expected, the image produced shows four quadrants, alternating light-dark-light- dark. As an optically active solution (corn syrup) is poured between them in a beaker, the image rotates and separates into a beautiful array of spectrum colors. See free video at flinnsci.com.
Concepts: Visible light spectrum, optical activity.
Time Required: 15 minutes
Materials Provided: Two pieces of polarized filter material and a detailed instruction sheet.
Note: A 600-mL, tall-form beaker, corn syrup, and an overhead projec- tor are needed.
Flame Test/Emission Spectroscopy—
Chemical Demonstration Kit
By: The Flinn Staff
Each element emits a specific wavelength of light, thus a characteristic color, when excited by a flame. This unique flame test kit produces better results and is easier to perform than the expensive platinum wire procedure. A laboratory burner is placed on top of a Petri dish which has a hole cut in its top. Inside the Petri dish a chemical reaction takes place, producing a gas. The gas rises, carrying some metallic ions into the burner flame. The burner flame becomes the characteristic color of the excited element. The vivid colors last several minutes, allowing students plenty of time to view the colored flame through Flinn C-SpectraTM. A specially designed can is placed over the labo- ratory burner to help direct the metallic ions and gas into the flame. Demonstration Notes and reproducible student worksheet included. Concepts: Absorption, emission, diffraction grating, flame tests, emis- sion spectra.
Time Required: 15 minutes
Materials Provided: Specially cut can, Petri dish bottoms, specially cut Petri dish top, 12 1"-square Flinn C-Spectra, hydrochloric acid solu- tion, mossy zinc, lithium chloride, sodium chloride, strontium chloride, barium chloride, potassium chloride, calcium chloride.
Is There Sodium in Bananas? Flame Test Demonstration Kit AP7334
Catalog No.
Description
Price/Each
AP7334
Is There Sodium in Bananas? Flame Test Demonstration Kit
$31.50
GP3019
Petri Dish, Borosilicate Glass, Pkg./6
47.25
Kaleidoscoptical Activity— Demonstration Kit
AP8781
Catalog No.
Description
Price/Each
AP8781
Kaleidoscoptical Activity—Demonstration Kit
$57.85
Flame Test/Emission Spectroscopy Kit—Chemical Demonstration Kit AP1716
Catalog No.
Description
Price/Each
AP1716
Flame Test/Emission Spectroscopy Kit— Chemical Demonstration Kit
$83.20