High School Chemistry Demonstrations

Interesting and Exciting Chemistry Demos

High school science students are hard to impress! Here's a list of top chemistry demonstrations to capture student interest and illustrate chemistry concepts.

This is an explosion resulting from adding about 3 pounds of sodium to water.
This is an explosion resulting from adding about 3 pounds of sodium to water. The reaction between sodium and water produces sodium hydroxide and heat. There can be an explosion of sodium metal and corrosive sodium hydroxide solution. Ajhalls, public domain

Sodium reacts vigorously with water to form sodium hydroxide. A lot of heat/energy is released! A very small amount of sodium (or other alkali metal) produces bubbling and heat. If you have the resources and space, a larger amount in an outdoor body of water forms a memorable explosion. You can tell people the alkali metals are highly reactive, but the message is driven home by this demo.

How To Do the Sodium in Water Demo More »

This water droplet on a hot burner is displaying the Leidenfrost effect.
This water droplet on a hot burner is displaying the Leidenfrost effect. Cryonic07, Creative Commons License

The Leidenfrost Effect occurs when a liquid droplet encounters a surface much hotter than its boiling point, producing a layer of vapor that insulates the liquid from boiling. The simplest way to demonstrate the effect is by sprinkling water on a hot pan or burner, causing the droplets to skitter away. However, there are fascinating demonstrations involving liquid nitrogen or molten lead.

Demonstrate the Leidenfrost Effect More »

Space-filling model of sulfur hexafluoride.
Space-filling model of sulfur hexafluoride. Ben Mills

Sulfur hexafluoride is an odorless and colorless gas. Although students know fluorine is extremely reactive and usually quite toxic, the fluorine is safely bound to sulfur in this compound, making it safe enough to handle and even to inhale. Two noteworthy chemistry demonstrations illustrate the heavy density of sulfur hexafluoride relative to air. If you pour sulfur hexafluoride into a container, you can float light objects on it, much like you would float them on water except the sulfur hexafluoride layer is completely invisible. Another demonstration produces the opposite effect from inhaling helium. If you inhale sulfur hexafluoride and speak, your voice will seem much deeper.

Learn To Use Sulfur Hexafluoride More »

This $20 is on fire, but it is not being consumed by the flames. Do you know how the trick is done?
This $20 is on fire, but it is not being consumed by the flames. Do you know how the trick is done?. Anne Helmenstine

Most high school chemistry demonstrations are hands-off for students, but this is one they can try at home. In this demonstration, 'paper' currency is dipped in a solution of water and alcohol and set alight. The water absorbed by the fibers of the bill protect it from ignition.

Make Money Appear To Burn More »

Chemistry Demonstration
Chemistry Demonstration. George Doyle, Getty Images

The Briggs-Rauscher oscillating clock (clear-amber-blue) may be the best known color change demo, but there are several colors of clock reactions, mostly involving acid-base reactions to produce the colors.

Classic Briggs-Rauscher Oscillating Clock
Water into Wine or Blood
Vanishing Valentine
Halloween or Old Nassau Reaction
Christmas Color Change Demo More »

If you disturb water that has been supercooled, it will suddenly crystallize into ice.
If you disturb water that has been supercooled or cooled below its freezing point, it will suddenly crystallize into ice. Vi..Cult..., Creative Commons License

Supercooling occurs when a liquid is chilled below it's freezing point, yet remains a liquid. When you do this to water, you can cause it to change to ice under controlled conditions. This makes for a great demonstration that students can try at home, too.

Supercool Water More »

This is a flask of elemental iodine vapor.
This is a flask of elemental iodine vapor. Matias Molnar

All you need is iodine and ammonia to make nitrogen triiodide. This unstable material decomposes with a very loud 'pop', releasing a cloud of violet iodine vapor. Other reactions produce violet smoke without the explosion.

Make Nitrogen Triiodide
Violet Smoke Demonstrations More »

The rainbow of colored fire was made using common household chemicals to color the flames.
The rainbow of colored fire was made using common household chemicals to color the flames. Anne Helmenstine

A colored fire rainbow is an interesting take on the classic flame test, used to identify metal salts based on the color of their emission spectra. This fire rainbow uses chemicals readily available to most students, so they can replicate the rainbow themselves. This demo leaves a lasting impression.

Make a Rainbow of Colored Fire More »