3 at-home chemistry experiments for Halloween

Julia Trowbridge

Editors note: Julia Trowbridge is the Public Relations coordinator for Colorado State University’s Chemistry Club.

It’s time to get spooky with science.


Colorado State University’s Chemistry Club hosted their annual “Halloween Spooktacular Show” with over 40 volunteers and around 1,100 guests this past weekend. The show contained a multitude of interactive experiments that everyone could try. Bugs and reptiles from CSU’s Entomology Club and the Zoological Discovery Center made an appearance and shows with more flashy demonstrations people shouldn’t try at home. 

From the “Halloween Spooktacular Show,” here are three hands-on Halloween themed experiments you can do at home.

Melting Witch

What you need: styrofoam, acetone and a beaker. Try a styrofoam ball and cone to create a cute little witch head.

What to do: Take the styrofoam, place it on a stick for safety, and dunk the styrofoam into the acetone. After a little while, the styrofoam will start to “melt,” and eventually disappear completely.

Why this works: Acetone is actually a really good solvent for styrofoam, so what you’re observing is the styrofoam dissolving into the acetone. This trick can help you recreate your own ‘Wizard of Oz’-style witch melting. 

Sharpie tie-dye

What you need: different colored sharpies, cloth quilting squares, rubbing alcohol (ethanol) and a pipette.

What to do: First, draw a spooky design on the cloth quilting square with various colored sharpies. After you’ve finished drawing your design, use the pipette to slowly drop the ethanol on the cloth. The ethanol will cause the colors from the sharpie to spread out in what looks like tie-dye.

Why it works: The dyes in the sharpie are polar, which means there are more electrons in one part of the molecule compared to the other, based on the structure and the elements in the molecule. Ethanol is also polar, so when the dye in the sharpie and the ethanol interact, the dye will move with the ethanol as the drop spreads outwards, creating the tie-dye design.


What you need: borax (powdered laundry detergent), water and clear craft glue.


What to do: Create a borax solution by mixing one cup of water to one-half teaspoon of borax. Slowly add this solution to your desired dollop size of clear craft glue until you get your desired slime consistency. 

Why it works: The clear craft glue contains polymer chains, which are long chains of carbon-carbon bonds. The borax reacts with these polymer chains to further connect these chains, giving it more of solid-like properties.

Collegian reporter Julia Trowbridge can be reached at entertainment@collegian.com or on twitter @chapin_jules.