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Acids, Bases and Indicators
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Acids, Bases and Indicators— Demonstration Kits
Flinn’s Exploring ChemistryTM—
Acids and Bases Package See page 31.
Acid–Base Titration with Conductivity—
Chemical Demonstration Kit
By: The Flinn Staff
Light up your students’ interest with this eye-catching demonstration! Explore precipitation, conductivity and acid–base chemistry, all in one fun demo! At first, the clear pink solution lights up the light bulb on the conductivity tester. As sulfuric acid is added, the light gradually fades and the solution turns milky white. If you continue to add acid, the light begins to brighten again! All solutions come ready made for easy use. A great kit to improve student understanding of these complex topics. Concepts: Acid and bases, conductivity, precipitation
Time Required: 20 minutes
Chemicals Provided: Barium hydroxide solution, phenolphthalein indicator solution and sulfuric acid.
Note: A conductivity sensor with a bulb is required and available separately.
Acid Strength and Electron Withdrawing Groups— Chemical Demonstration Kit By: The Flinn Staff
Take the weak acid vinegar, substitute three chlorine atoms for the three hydrogen atoms, and remarkably, the new acid is 10,000 times more powerful! Acids vary greatly in their strength—their ability to ionize or produce H+ ions when dissolved in water. In this demonstration, the effect of electron-withdrawing groups on the strength of weak acids is shown by preparing half-neutralized solutions of a series of chlorinated acetic acids and then using indicators to compare their resulting pH values. Unique demonstration provides a colorful lesson in recogniz- ing and identifying trends or patterns in chemical properties. Excellent review of pKa determinations! Demonstration Notes, along with both a reproducible student worksheet and answer sheet are included. Concepts: Acid strength, weak acid, conjugate base, equilibrium constant and inductive effect.
Time Required: 20 minutes
Materials Provided: Acetic acid solution, chloroacetic acid solution, trichloroacetic acid solution, sodium hydroxide solution, phenolphtha- lein indicator solution, orange IV indicator solution, bromphenol blue indicator solution, methyl red indicator solution, universal indicator solution, disposable Petri dishes, disposable pipets.
Properties of Buffer Solutions—General Chemistry Guided-Inquiry Experiment See page 19.
Acid–Base Titration with Conductivity—Chemical Demonstration Kit AP8482
Catalog No.
Description
Price/Each
AP8482
Acid–Base Titration with Conductivity— Chemical Demonstration Kit
$29.50
Acid Strength and Electron Withdrawing Groups— Chemical Demonstration Kit
AP7246
ACIDS, BASES AND INDICATORS— DEMONSTRATION KITS continued on next page.
Catalog No.
Description
Price/Each
AP7246
Acid Strength and Electron Withdrawing Groups—Chemical Demonstration Kit
$46.25
Large Demonstration Tray
Perform your fun but messy demonstrations in our extra-large fiberglass tray. Rounded edges and 5-cm lip catch the overflow and make cleanup a breeze. Also useful for dispensing chemicals to minimize and contain spills. Fiberglass resists acids, bases, and most solvents—and it won’t corrode or warp! Size 76 cm L x 51 cm W x 5 cm D.
See free video at flinnsci.com.
Catalog No.
Description
Price/Each
AP5429
Demonstration Tray, Large
$89.50