Energetic Light

Demonstration Kit

Introduction

Two solutions are combined to produce a beautiful chemiluminescence that lasts approximately 10 minutes.

Concepts

  • Chemiluminescence
  • Oxidation–reduction

Materials

Energetic Light solution, 500 mL*
Hydrogen peroxide solution, 3%, H2O2, 50 mL*
Potassium ferricyanide solution, 0.6%, K3Fe(CN)6, 500 mL*
Beakers, 250-mL, 2
Graduated cylinder, 10-mL
Graduated cylinder, 100-mL
Stirring rod
*Materials included in kit.

Safety Precautions

The hydrogen peroxide solution is an oxidizer and a skin and eye irritant. Potassium ferricyanide solution is a mild irritant. Contact with strong acids may liberate toxic hydrogen cyanide gas; avoid contact with strong acids. Wear chemical splash goggles, chemical-resistant gloves and a chemical-resistant apron. Please review current Safety Data Sheets for additional safety, handling and disposal information.

Disposal

Please consult your current Flinn Scientific Catalog/Reference Manual for general guidelines and specific procedures, and review all federal, state and local regulations that may apply, before proceeding. The resulting solution may be oxidized with household bleach as the final step in the procedure and flushed down the drain with excess water according to Flinn Disposal Method #14.

Prelab Preparation

Add 70 mL of the 0.6% potassium ferricyanide solution and 7 mL of 3% hydrogen peroxide solution to one 250-mL beaker. Add 70 mL of the Energetic Light solution to a second 250-mL beaker. Note: The Energetic Light solution is very viscous.

Procedure

  1. Darken the room completely.
  2. While stirring with a stirring rod, add the potassium ferricyanide/hydrogen peroxide solution to the Energetic Light solution.
  3. Observe the chemiluminescence. Stir the solution occasionally to prolong the light reaction.

Student Worksheet PDF

13038_Student1.pdf

Teacher Tips

  • Make sure you stir the energetic light solution while you are adding the 0.6% potassium ferricyanide solution. This will add to the longevity of the chemiluminescence.
  • Chemiluminescence is not a bright light; it is more of a glow. The darker the room, the brighter the glow will appear.

Correlation to Next Generation Science Standards (NGSS)†

Science & Engineering Practices

Developing and using models
Constructing explanations and designing solutions
Engaging in argument from evidence

Disciplinary Core Ideas

MS-PS1.A: Structure and Properties of Matter
MS-PS1.B: Chemical Reactions
MS-PS3.D: Energy in Chemical Processes and Everyday Life
HS-PS1.A: Structure and Properties of Matter
HS-PS1.B: Chemical Reactions
HS-PS3.D: Energy in Chemical Processes

Crosscutting Concepts

Cause and effect
Systems and system models
Energy and matter
Stability and change

Performance Expectations

MS-PS1-2. Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.
HS-PS1-1. Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.
HS-PS1-2. Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.

Answers to Questions

  1. Describe what happened in this demonstration.

    Two solutions were mixed together. The resulting yellow-green mixture glowed for about ten minutes.

  2. In chemiluminescence, a molecule in an “excited” state (i.e., electrons are at a high energy level) is produced. The electrons in the molecule then must return to their stable state (i.e., lower energy level). Explain how this is linked to the production of light.

    When an electron drops to a lower energy level, energy must be released. This energy is released in the form of light.

  3. Define chemiluminescence. Give an example of chemiluminescence found in nature.

    Chemiluminescence is a process in which light is produced through a chemical reaction. An example of chemiluminescence found in nature is the firefly.

Discussion

Chemical luminescence, or chemiluminescence, is a process by which chemical energy is converted into light energy. The chemical reaction generates a product in an intermediate excited state (the electrons are at a higher energy level than in the ground state. When the electrons fall from that excited state to the more stable ground state, energy is released in the form of light.

A + B → C + D* → D + light

The chemiluminescence reaction follows an energy diagram like this:
{13038_Discussion_Figure_1}

References

Special thanks to Tom Russo for providing us with the instructions for this activity.

Shakhashiri, B. Z. Chemical Demonstrations: A Handbook for Teachers of Chemistry, Vol. 1: The University of Wisconsin: Madison, 1983, pp 161–167.

Recommended Products

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AP8978 Energetic Light—Chemical Demonstration Kit

†Next Generation Science Standards and NGSS are registered trademarks of Achieve. Neither Achieve nor the lead states and partners that developed the Next Generation Science Standards were involved in the production of this product, and do not endorse it.