As ammonia gas dissolves in water, the pressure inside the inverted flask is lowered. This decrease in pressure draws the two solutions into the flask, which react to form a glowing chemiluminescent ammonia fountain.
- Solubility of gases
Ammonium carbonate, (NH4)2CO3, 0.5 g*
Ammonium hydroxide, NH4OH, conc., 2–3 mL
Copper(II) sulfate, CuSO4•5H2O, 0.4 g*
Hydrogen peroxide, H2O2, 6%, 25 mL*
Luminol, 0.2 g*
Sodium bicarbonate, NaHCO3, 24 g*
Sodium carbonate, Na2CO3, 4 g*
Erlenmeyer flasks, 1-L, 2
Glass tubing, 15–20 cm
Ring stand with clamp
Round-bottom flask, 1-L
Rubber stopper, 2-hole
Rubber tubing, 45 cm
Tubing connector, T-shaped*
*Materials included in kit.
Ammonia vapor is severely toxic and irritating by inhalation and may be fatal. Use only under a fume hood. Ammonia is also a moderate fire risk. 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.
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 remaining solution may be flushed down the drain with excess water according to Flinn Suggested Disposal Method #26b.
- In a 1-L Erlenmeyer flask, dissolve 4 g of sodium carbonate in approximately 600 mL of distilled water. Add 0.2 g of luminol, stir to dissolve. Add 24 g of sodium bicarbonate, 0.5 g of ammonium carbonate and 0.4 g of copper(II) sulfate. Stir to dissolve. Dilute to 1000 mL with distilled water. Stir. This is Solution A.
- In a second 1-L flask, add 25 mL of 6% hydrogen peroxide. Dilute to 1000 mL with distilled water and mix well. This is Solution B.
- Prepare the two-hole rubber stopper with water in the medicine dropper as shown in Figure 1. Use rubber tubing to connect the glass tubing pieces.
- Under an operating fume hood, add a few milliliters of concentrated ammonium hydroxide to the round-bottom flask and place it on a warm hot plate until the liquid evaporates.
- Stopper and invert the flask. Clamp it to the ring stand as shown in the diagram.
- Attach the rubber tubing from the flask to the T-shaped tubing connector and from each side of the connector to the two 1-L Erlenmeyer flasks full of solutions.
- Turn down the lights. The darker the room, the more dramatic the effect.
- Initiate the reaction by squeezing the medicine dropper and allowing a few drops of water to enter the flask.
- The partial vacuum produced by the ammonia gas dissolving in the water will draw the solutions up into the round bottom flask. As the two solutions mix, they create a beautiful chemiluminescent effect.
Correlation to Next Generation Science Standards (NGSS)†
Science & Engineering Practices
Asking questions and defining problems
Developing and using models
Constructing explanations and designing solutions
Disciplinary Core Ideas
MS-PS1.A: Structure and Properties of Matter
MS-PS1.B: Chemical Reactions
MS-PS4.B: Electromagnetic Radiation
HS-PS1.A: Structure and Properties of Matter
HS-PS1.B: Chemical Reactions
HS-PS4.B: Electromagnetic Radiation
Cause and effect
Systems and system models
Energy and matter
Stability and change
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-PS4-2. Develop and use a model to describe that waves are reflected, absorbed, or transmitted through various materials.
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
- Draw a diagram of the set-up for this demonstration. Describe what happened in this demonstration.
Student answers may vary. Several drops of water were squeezed through a medicine dropper into the round-bottom flask. The solutions inside the two Erlenmeyer flask were drawn up into the round-bottom flask, creating a fountain. The fountain glowed.
- Explain how the fountain effect inside the round-bottom flask occurred.
The round-bottom flask contained ammonia gas, which is soluble in water. When water was injected into the flask some of the ammonia dissolved, decreasing the pressure inside the flask. The pressure drop caused some of the two solutions into the flask, which lowers the pressure even more. The difference in pressure is great enough to create a fountain effect.
- Define chemiluminescence. Give an example of chemiluminescence found in nature.
Chemiluminescence is a process by which energy of a chemical rxn is converted to light energy. An example of this that is found in nature is the firefly.
Ammonia fountains dramatically show the solubility of ammonia gas in water. Initially, the flask is full of ammonia gas. When a few drops of water are injected into the system, some of the ammonia dissolves in the water. This lowers the pressure inside the flask, drawing up the two solutions. When the solutions enter the flask, more ammonia gas will dissolve, increasing the pressure difference to such a degree that a fountain effect is created.
Chemiluminescence is a process by which energy of a chemical reaction is converted into light energy. Light is produced when electrons drop from an excited or high energy level to a stable or lower energy level. In chemiluminescence, a reaction produces a molecule that is in an excited state. As the electrons in this molecule return to their ground state, energy is released in the form of light. The reaction of luminol with the other chemicals to create the chemiluminescent effect is shown.
Shakhashiri, B. Z. Chemical Demonstrations; University of Wisconsin: Madison, 1985, p 156–167.
Thomas, N. J. Chem. Ed. 1990, 67, 431.
||Chemiluminescent Ammonia Fountain—Chemical Demonstration Kit
||Water, Distilled, 4 L
||Flask, Erlenmeyer, Borosilicate Glass, 1000 mL
||Glass Tubing, Soft Glass, 24" Lengths, 6 mm o.d., 4 mm i.d., Pkg. of 10
||Pipet, Medicine Dropper
||Ring Support, with Rod Clamp, 4"
||Synthware® Flask, Round Bottom, Single Neck, 24/40, 1000 mL
||Rubber Stoppers, 1 lb, Size #10, Black, Two-Hole
||Synthetic Rubber Tubing, Latex-Free, 10-Ft Length