Create Silver-Mirrored Christmas Ornaments with a Redox Reaction
Create silver ornaments with your students using a chemical process similar to antique mirroring techniques. In this festive activity, silver is plated onto the interior surface of a glass vial via a redox reaction. In the reaction, dextrose is oxidized to gluconic acid, and silver ions are reduced to metallic silver.
Topics covered: redox reactions, Lewis acids and bases, organic structures, complexes, and stoichiometry.
Materials
- Acetone
- 0.5 M Silver Nitrate
- 1.5 M Ammonium Nitrate (prepare fresh for each demo)
- 5% Dextrose Solution
- 3 M Sodium Hydroxide
- Sodium Chloride (for waste)
- Disposable Pipets
- Glass Vials, 2 dram
- Beaker, 600 mL
- Glass Stir Rod
- Deionized Water
- Tap Water
- Curling ribbon (optional)
- Ornament hangers or paper clips (optional)
Safety
- Keep acetone away from heat, sparks, and flame.
- Keep ammonium nitrate away from clothing and other combustible materials.
- Sodium hydroxide causes skin and eye burns; avoid contact with skin, eyes, and clothing.
- The waste products from this activity can form explosive silver compounds. After the demonstration, mix the silver waste produced in this activity in a saturated sodium chloride solution to produce stable silver chloride.
- The mirrored silver vial made in this activity is for decorative purposes only and should not be used for food or drink.
Additional Reading: Investigating Phenomena: How Is the Silver Formation Explained?
Teacher preparation
- Put on safety glasses and gloves.
- Combine about 100 mL of tap water and 40 g of sodium chloride in a 600-mL beaker. Stir to dissolve most of the salt. This beaker of saltwater serves as the waste container for all silver-containing waste.
Student procedure
- Put on safety glasses and gloves.
- Combine about 100 mL of tap water and 40 g of sodium chloride in a 600-mL beaker. Stir to dissolve most of the salt. This beaker of saltwater serves as the waste container for all silver-containing waste.
- Prepare a 5% dextrose solution by adding 30 mL of deionized water to 1.5 g of dextrose. Prepare the ammonium nitrate.
- Using a pipet, transfer about 2 mL of acetone to the vial, and secure the lid. Shake the vial to distribute the acetone and cover the interior of the vial. Remove the lid, empty the vial into a waste container, and allow the lid and vial to air dry.
- Using a pipet, transfer 2.0 mL of silver nitrate to the vial.
- Using a pipet, transfer 2.0 mL of ammonium nitrate to the vial.
- Using a pipet, transfer 2.0 mL of dextrose solution to the vial.
- Using a pipet, transfer 2.0 mL of sodium hydroxide to the vial.
- Put the lid on the vial, and swirl the vial for about 2 minutes to distribute the solution over the entire interior surface of the vial. You should begin to see a silver coating form on the inside of the vial.
- After swirling for 2 minutes, remove the lid from the vial, and pour the vial’s contents into the waste beaker of saltwater. Important: To prevent formation of explosive silver compounds, it is important that the waste container contain a saturated sodium chloride solution. See step 4.
- Rinse the inside of the vial with tap water and pour the contents into the waste beaker. Allow the inside of the bottle to dry before sealing lid.
- The silver vials can easily be strung into holiday decorations using twine, wire, or string.