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Sealed tubes of a mixture of NO₂ and N₂O₄ gas are placed in ice water and in boiling water, and an instant change in the equilibrium system is demonstrated, according to Le Chatelier’s Principle.

An old bomb calorimeter made by the Parr Instrument Company for show-and-tell. Circa 1964.

What it Shows

Cyclohexane vapor catches on fire when it flows downwards to a burning candle at the bottom of a ramp.

How it Works

Cyclohexane is a clear, organic liquid with a formula of C₆H₁₂.

Because cyclohexane is a nonpolar molecule with only weak...

What it Shows

An inverted trash can is launched into the air by an exploding bottle of liquid nitrogen.

Link to Liquid Nitrogen Trashcan video can be found here https://harvard.hosted.panopto.com/Panopto/Pages/Viewer.aspx?id=6f33f468-528c-4ab5-acd6...

When two rusty iron balls—one wrapped in aluminum foil—are struck together, sparks and light are given off in this small scale thermite reaction.

Video of Microscope Thermite Reaction can be found at https://www.youtube.com/watch?v=V5VXt0hZOc8

What it

...

A solution with bromothymol blue indicator changes from blue to yellow as the instructor blows into the liquid with a straw.

Video of Professor's Acid Breath can be found here https://youtu.be/hfhNZEzBEtg

What it Shows

A person’s breath contains carbon...

“Under the microscope one, to some extent, immediately sees a part of thermal energy in the form of mechanical energy of the moving particles.” —A. Einstein 1915

What it Shows

Tiny latex spheres in water, viewed under a microscope, undergo a kind of...

What it shows

An unopened can of Diet Coke floats in a tank of water, whereas the same cannot be said for a can of regular Coca-Cola.

Setting it up

Use the smallest available tank. If unopened cans are not already in the Prep Room, they can be procured from...

What it shows

Does the level of the ocean rise or fall when a cannon ball is tossed overboard? A question of displacement.

How it works

A difficult effect to see at sea, but it becomes clear by taking some parameters to extremes. Reducing the ocean to 12L in...

What it shows

We have three 20 oz. soda bottles, one filled with water, one filled with sand, and one filled with air. A spring scale shows the water-filled bottle to weigh approximately 6N in air, and nearly 0N when it is fully submerged in a large...