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Chemical Reactions
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Chemical Reactions—Demonstration Kits,
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Classifying Chemical Reactions— Multi-Demonstration Kit
By: The Flinn Staff
Students love spectacular chemical reactions, but do they always know what they are seeing? Use these ten targeted demonstrations to help students become proficient in identifying the five different types of chemical reactions.
Single Replacement
• Stunning silver crystals completely cover the wire surface and the solution turns blue when a copper wire coil is suspended in a silver nitrate solution.
• Aluminum dissolves, copper metal precipitates, and things really heat up when aluminum foil is added to copper(II) chloride.
Double Replacement
• Mixing copper(II) chloride and sodium phosphate produces a beautiful turquoise precipitate.
• An “avalanche” of snow white precipitate suddenly appears when sodium chloride and silver nitrate are combined.
• Mix milk of magnesia (MOM) with universal indicator, add hydro- chloric acid solution and watch a rainbow appear and disappear as the antacid neutralizes the simulated stomach acid.
Combination
• Adding water to solid calcium oxide gives calcium hydroxide, along with enough heat to fry an egg.
• Burning steel wool provides a glowing demonstration of the exother- mic combination reaction of iron and oxygen.
Decomposition
• Fill a Petri dish with salt and universal indicator solution, attach alliga- tor clips and a battery, and observe a rainbow of color changes as the water molecules split apart.
• Use the “wine airlock” included with the kit to identify the gas and analyze the color changes produced when solid copper(II) carbonate is heated.
Combustion
• Add a little isopropyl alcohol to a soda bottle, ignite the vapors, and “whoosh”! The combustion of isopropyl alcohol and oxygen creates a rush of gases and a spectacular blue flame.
Perform all the demonstrations together as an introduction or as a review of reaction types, or space them over several days to focus on a specific type of chemical reaction. Demonstration Notes, along with a reproducible student worksheet, are included.
Concepts: Combination reaction, combustion, decomposition, electrol- ysis, exothermic reaction, oxidation-reduction, precipitation reaction, single and double replacement.
Time Required: One full class period
Materials Provided: Aluminum foil, calcium oxide, copper(II) chlo- ride solution, isopropyl alcohol, sodium chloride/universal indicator solution, sodium phosphate solution, hydrochloric acid solution, bromthymol blue indicator solution, copper(II) carbonate, copper wire, acetone, milk of magnesia, silver nitrate solution, sodium chloride solu- tion, universal indicator solution, steel wool, wine airlock, 9-V battery, battery leads with alligator clips, fifteen disposable pipets and seven disposable Petri dishes.
Note: Some common laboratory equipment is required, but not provided.
Flinn’s Exploring ChemistryTM— Chemical Reactions Package See page 29.
Classifying Chemical Reactions—Multi-Demonstration Kit AP6605
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 chemi- cals 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
Catalog No.
Description
Price/Each
AP6605
Classifying Chemical Reactions— Multi-Demonstration Kit
$152.05
CHEMICAL REACTIONS—DEMONSTRATION KITS continued on next page.