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Properties of Liquids and Solids
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Properties of Liquids and Solids— Demonstration Kits, continued
Lopsided Liquid—
Chemical Demonstration Kit
By: The Flinn Staff
A free-flowing U-shaped tube contains what appears to be a homo- geneous blue liquid, yet the liquid levels in the sides of the tube are unequal. No tricks involved—just density! This simple demonstration is guaranteed to heighten student interest on the concepts of density, specific gravity and other related topics. Teacher Demonstration Notes included.
Concepts: Density, specific gravity, observation.
Time Required: 10 minutes
Materials Provided: Glass U-tube, isopropyl alcohol, blue food dye. Note: A ring stand and clamp are required and available separately.
Mass Is Conserved—Volume Is Not!
Chemical Demonstration Kit
By: The Flinn Staff
50 + 50 doesn’t always equal 100! Many students have heard that matter is not created or destroyed. This concept relates to mass but not to volume or moles. Show students that adding two identical volumes does not always give twice the volume when combined. Three differ- ent demonstrations are performed to show that in the combination of reactants different intermolecular bonding and densities may result— leaving the final volume a discrepant event. Demonstration kit comes complete with instructions, teaching information, sample data, a repro- ducible student handout, and answers for the teacher.
Concepts: Conservation of mass, intermolecular forces–hydrogen bonding, neutralization, density.
Time Required: 15–20 minutes
Chemicals Provided: Ethyl alcohol, hydrochloric acid, and sodium hydroxide.
See free video at flinnsci.com.
Red, White and Blue Density Column—
Chemical Demonstration Kit
By: The Flinn Staff
Create a beautiful, red, white and blue density column to demonstrate the salting-out effect, relative density and the miscibility of organic solvents with water. The density column contains three liquid layers consisting of toluene, methyl alcohol and water. Methyl alcohol is “salted out” and separated from water by adding potassium carbon- ate. The water is dyed blue with copper(II) sulfate, and the toluene is colored red with Sudan III. Why don’t the methyl alcohol and toluene mix? Store the multicolored density column for up to a month in the glass bottle with chemical-resistant cap included with the kit. The attention-getting display is sure to generate lots of interest, giving you a great lead-in for lessons on density, polarity or solubility!
Concepts: Solubility, density, miscible and immiscible liquids, salting- out effect.
Time Required: 30 minutes
Materials Provided: Copper(II) sulfate, methyl alcohol, potassium carbonate, Sudan III dye, toluene, glass demonstration bottle with chemical-resistant cap.
Note: Perform this demonstration in a fume hood or well-ventilated lab.
PROPERTIES OF LIQUIDS AND SOLIDS—DEMONSTRATION KITS continued on next page.
Lopsided Liquid— Chemical Demonstration Kit AP6649
Catalog No.
Description
Price/Each
AP6649
Lopsided Liquid—Chemical Demonstration Kit
$18.55
Mass Is Conserved—Volume Is Not! Chemical Demonstration Kit AP7445
Catalog No.
Description
Price/Each
AP7445
Mass Is Conserved—Volume Is Not! Chemical Demonstration Kit
$19.15
Catalog No.
Description
Price/Each
AP7089
Red, White and Blue Density Column— Chemical Demonstration Kit
$31.15
Red, White and Blue Density Column—Chemical Demonstration Kit AP7089