Zinc Pyrotechnics


A spectacular “fireworks” display is initiated by adding just two drops of water to a mixture of dry chemicals.


  • Oxidation–reduction reactions
  • Autocatalysis
  • Decomposition reactions
  • Catalysis (optional—see Tips section)


Ammonium chloride, NH4Cl, 10 g*
Ammonium nitrate, NH4NO3, 100 g*
Zinc dust, Zn, 100 g*
Water, distilled, 1 mL
Beaker, Pyrex®, 50-mL
Ceramic fiber square or heat-resistant surface
Fume hood
Medicine dropper or Beral pipet
Stirring rod
*Materials included in kit.

Safety Precautions

Ammonium nitrate is a strong oxidizer; may explode if heated under confinement or at temperatures of 250 °C; toxic by ingestion and inhalation; skin, eye, and respiratory irritant. Zinc dust can be a dangerous fire risk; may form explosive mixture with air. If allowed to get damp in a confined bottle, heat will be generated and the mixture may even possibly ignite. Ammonium chloride is toxic by ingestion. Zinc oxide fumes, one of the products of the reaction, can be toxic and severely irritating. Do not premix the ingredients before the demonstration. They can react prematurely and, if in a closed container, explode violently. This reaction should only be done in an operating fume hood or possibly out-of-doors due to amount of smoke produced. This reaction also produces a great deal of heat so it is imperative that an insulating material such as the ceramic fiber square be placed under the beaker. Do not scale this reaction up. The demonstrator should wear chemical splash goggles, a chemical-resistant apron and chemical-resistant gloves. Students should wear chemical splash goggles. Please review current Safety Data Sheets for additional safety, handling and disposal information.


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 solid products of this reaction may be disposed of in a landfill according to Flinn Suggested Disposal Method #26a.


  1. Remove all combustible materials from the fume hood. Place the 50-mL Pyrex beaker on a ceramic fiber square or other heat-resistant surface inside fume hood.
  2. Add 8 g of ammonium nitrate, 8 g of zinc dust, and 1 g of ammonium chloride to the beaker; mix with the stirring rod.
  3. Using the medicine dropper or a Beral pipet, add two drops of distilled water to the beaker and quickly lower the hood shield. Do not add more than two drops.
  4. Observe the reaction and “fireworks!”

Student Worksheet PDF


Teacher Tips

  • This demonstration can be modified to provide a dramatic example of catalysis. Prepare two 50-mL Pyrex beakers with the ammonium nitrate and zinc dust, as described, but only include ammonium chloride in one of the beakers. Add the two drops of water first to the beaker without ammonium chloride. It will produce smoke and vapor, but will probably not produce flame. After the reaction is complete, add two drops of water to the second beaker. The reaction will proceed much more quickly and will produce smoke, sparks, and flames—the “eruption.”
  • This kit provides enough materials to perform this modification five times.

Correlation to Next Generation Science Standards (NGSS)

Science & Engineering Practices

Developing and using models
Obtaining, evaluation, and communicating information
Planning and carrying out investigations

Disciplinary Core Ideas

MS-PS1.A: Structure and Properties of Matter
MS-PS3.A: Definitions of Energy
HS-PS1.A: Structure and Properties of Matter
HS-PS3.A: Definitions of Energy

Crosscutting Concepts

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

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.
MS-PS1-4: Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.
HS-PS2-2: Use mathematical representations to support the claim that the total momentum of a system of objects is conserved when there is no net force on the system.
HS-PS1-4: Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.
HS-PS3-2: Develop and use models to illustrate that energy at the macroscopic scale can be accounted for as a combination of energy associated with the motion of particles (objects) and energy associated with the relative position of particles (objects).
HS-PS3-4: Plan and conduct an investigation to provide evidence that the transfer of thermal energy when two components of different temperature are combined within a closed system results in a more uniform energy distribution among the components in the system (second law of thermodynamics).

Answers to Questions

  1. Describe what happened in this demonstration.

    Solid ammonium nitrate, zinc dust and ammonium chloride were mixed together in a small beaker in a fume hood. Two drops of water were added to the beaker. Almost immediately, the mixture in the beaker produced intense sparks and flames as well as a white smoky cloud.

  2. The exact mechanism of this reaction is unknown, but it is believed to begin with the heat produced by the addition of water to zinc melting the solid ammonium nitrate.
    1. Write a balanced chemical equation showing the volatilization of liquid ammonium nitrate into nitrous oxide and water.

      NH4NO3(l) → N2O(g) + H2O(g)

    2. The heat from the volatilization reaction causes the zinc to dissolve in the ammonium nitrate. Write a balanced chemical equation for this step.

      Zn(s) + NH4NO3(s) → N2(g) + ZnO(s) + 2H2O(g)

    3. Then, a cloud of white and yellow particles is produced. What do you think this cloud is?

      The cloud is solid zinc oxide, produced when the zinc dissolved in the ammonium nitrate. The energy from that reaction caused the zinc oxide to disperse into a cloud.

  3. Looking over the reaction as it is described above, notice that one of the solids in the original beaker is nowhere mentioned. Propose an idea for what the purpose of the ammonium chloride was.

The ammonium chloride may have served as a catalyst for any of the steps in the reaction, most likely the first. It may be why the reaction happened almost immediately after the water was added to the mixture in the beaker.


The mechanism of this reaction is complex. It is believed that the heat produced by the addition of water to the zinc dust melts the ammonium nitrate. Once melted, ammonium nitrate volatilizes, producing N2O and H2O. This reaction is catalyzed by chloride ions:


The energy change for the volatilization of ammonium nitrate to nitrous oxide and water is reported to be –23 kJ/mol. As the volatilization proceeds, the heat produced causes the zinc to dissolve in the molten ammonium nitrate. This leads to the rapid oxidation of the zinc, possibly according to the reaction:

Zn(s) + NH4NO3(s) → N2(g) + ZnO(s) + 2H2O(g)

The energy change for this reaction has been calculated to be –466.5 kJ/mol. This tremendous amount of energy produced causes the dispersal of zinc oxide as a white cloud and yellow/white particulate matter.


Cotton, F. A. and Wilkinson, G. Advanced Inorganic Chemistry: A Comprehensive Text; John Wiley and Sons: New York, 1980; p 417.

Shakhashiri, B. Z. Chemical Demon stra tions: A Handbook for Teachers in Chemistry; University of Wisconsin: Madison, WI; 1989; Vol. 1, p 51–52.

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.