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Solutions and Solubility
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Solutions and Solubility—Demonstration Kits,
continued
pH and Protein Solubility—
A Reversible Demonstration Kit
By: The Flinn Staff
Demonstrate the properties of proteins and the effect of pH on protein solubility with this colorful and reversible activity. Proteins contain many acidic and basic groups that have different structures at different pH values. When acids and bases are added to a protein solution, the solubility of the protein changes drastically. This demonstration looks at the acid–base and solubility properties of casein, the main protein in milk. The structure of the protein at different pH values is discussed. Demonstration Notes included.
Concepts: Proteins, isoelectric point, solubility, pH.
Time Required: 15 minutes
Chemicals Provided: Casein, hydrochloric acid solution, sodium hydroxide solutions, universal indicator.
Catalog No.
Description
Price/Each
AP6692
pH and Protein Solubility— Reversible Demonstration Kit
$23.50
Serial Dilution Demonstration Model
By: The Flinn Staff
What does one part per thousand look like? Make the
concepts of concentration and serial dilution more concrete for your students. Unique activity model simulates the process of serial dilu- tion as a stock “solution” of yellow beads is diluted with a blue bead “solvent.” Students will gain a better understanding of the concept of dilution as 1/10, 1/100, 1/1000, 1/10,000 and 1/100,000 simulated solu- tions are prepared. The beads from each dilution step are prominently displayed in durable demonstration tubes placed in a transparent display rack. Kit includes enough beads to repeat the activity at least 25 times, 5 demonstration tubes and caps, durable demonstration rack, and detailed instructions.
Solubility Patterns—
Chemical Demonstration Kit
By: The Flinn Staff
Are there any patterns or periodic trends in the solubility of alkaline earth metal compounds? Recreate the solubility pattern of the alkaline earth metal chlorides with four testing reagents in a microscale reaction plate on an overhead projector. The periodic trend instantly reveals itself. Two worksheets offer a valuable review of double replacement reactions and net ionic equations. Demonstration Notes included.
Concepts: Alkaline earth metals, periodic trends, solubility rules, double replacement reactions.
Time Required: 15 minutes
Chemicals Provided: Barium chloride solution, calcium chloride solution, magnesium chloride solution, strontium chloride solution, ammonium oxalate solution, potassium iodate solution, sodium carbon- ate solution, sodium sulfate solution.
See free video at flinnsci.com.
Serial Dilution Demonstration Model AP7515
pH and Protein Solubility—A Reversible Demonstration Kit AP6692
Catalog No.
Description
Price/Each
AP7515
Serial Dilution Demonstration Model
$55.70
Catalog No.
Description
Price/Each
AP6353
Solubility Patterns— Chemical Demonstration Kit
$52.75
SOLUTIONS AND SOLUBILITY—DEMONSTRATION KITS continued on next page.
Solubility Patterns—Chemical Demonstration Kit AP6353