Monthly Archives: September 2017

Goldenrod paper is a special paper containing dyes that react to pH change. A basic pH makes the paper appear to bleed. — Goldenrod paper is a special paper that drips blood! Really, it’s not blood, just a safe red liquid that resembles it. The paper contains a pH indicator that turns red in the presence of a base. You can use it to demonstrate pH indicators or for a spooky Halloween science […]

Bleeding Goldenrod Paper – Halloween Science Project

This entry was posted on September 11, 2017 by Anne Helmenstine (updated on September 26, 2021)

While lettuce and tomato may get slimy, a burger made with a bun, meat, and cheese won't rot. — If you’re up for a bit of scientific experimentation, you can get a McDonald’s hamburger, leave it on the counter, and prove to yourself it won’t appear to rot or decompose over time. Alternatively, you can skip the experiment and trust me on this, as a parent of a child […]

Why McDonald’s Hamburgers Don’t Decompose

This entry was posted on September 11, 2017 by Anne Helmenstine (updated on May 17, 2021)

Red cube — A volume conversion can be difficult to understand if you try to grasp the problem all in one step. Many volume conversion problems give the student a series of linear distances with one set of units, but want the volume in a different set of units. At first glance, this […]

Cubic Feet to Liters Volume Conversion Example Problem

This entry was posted on September 10, 2017 by Todd Helmenstine (updated on May 17, 2021)

This wax model volcano illustrates many of the processes that occur in real volcanoes. — This wax and sand volcano is a realistic model volcano that is easy to make and erupts much like a real volcano. The volcano is extremely simple to make and interesting to watch. Wax “lava” forms a volcano in sand, eventually erupting into the atmosphere, which is water in this […]

Wax Volcano Demonstration – A Realistic Model Volcano Recently updated !

This entry was posted on September 9, 2017 by Anne Helmenstine (updated on October 1, 2023)

Red Fire Pumpkin — What’s better than a regular Halloween jack o’ lantern? How about one that shoots out red fire? The red flames are easy to produce and last about an hour. They shoot up 2-3 feet into the air and range from orange to vivid red. Here’s how to do it: Red […]

Make a Halloween Pumpkin That Shoots Red Flames

This entry was posted on September 9, 2017 by Anne Helmenstine (updated on October 25, 2021)

The self-carving pumpkin demonstration involves carving a jack-o-lantern face using an explosive chemical reaction. — Self-Carving Halloween Jack-o-Lantern That Won’t Blow Up The self-carving Halloween pumpkin project uses chemistry to carve a jack-o-lantern face. The traditional version of the project is somewhat dangerous, so here’s how to perform a safe version of the project. Safe Self-Carving Pumpkin Materials If you can get it, this project […]

Safe Self-Carving Pumpkin Project

This entry was posted on September 9, 2017 by Anne Helmenstine (updated on May 17, 2021)

Close your eyes and imagine the color bluish-yellow — not green, but a color that appears both blue and yellow at once. Can you imagine reddish-green? If you mixed red and green paints, you’d end up with a brownish color rather than a color that you’d describe as both red […]

How Impossible Colors Work (And How to See Them)

This entry was posted on September 8, 2017 by Anne Helmenstine (updated on May 17, 2021)

A cockroach survives radiation better than a human, but it's not immune to the heat of an atomic bomb. (Amada44) — Cockroaches seem pretty indestructible, at least compared to us puny humans. They can live for a week without a head, survive a month without food, and appear unaffected inside an operating microwave oven. While it’s true the insects can survive harsh environments, can they really live through the detonation of […]

Can Cockroaches Survive a Nuclear Bomb?

This entry was posted on September 7, 2017 by Anne Helmenstine (updated on May 17, 2021)

(image: Burst) — Do you have hard water? If you do, you may have a water softener to help protect your plumbing from scale buildup, prevent soap scum, and lessen the amount of soap and detergent needed for cleaning. You’ve probably heard that cleansers work better in soft water than in hard water, […]

Why It’s Harder to Rinse Soap in Soft Water

This entry was posted on September 6, 2017 by Anne Helmenstine (updated on October 11, 2022)