public understanding

About a decade ago, I wrote briefly about the interesting experiment of throwing boiling hot water into air that is below -18°C (0°F) (see Ice Clouds).

Many have asserted that the water we drink is exactly the same water that has been eliminated from the bodies of humans and animals from the past. The argument goes that water excreted from our bodies by exhalation or urine ultimately ends up back in the water cycle.

The floating soap bubble¹ is an experiment that is very easy to set up and carry out (Video 1).

Jet-Puffed color changing marshmallows are an interesting new product that is available on the shelves of grocery stores through the end of September.¹ The color of these marshmallows changes when exposed to heat: the blue version turns green, while the pink version turns orange.

The chemistry demonstration called the self-carving pumpkin¹ is a blast (no pun intended) to conduct around Halloween. To prepare this experiment, a jack-o-lantern face is carved into a pumpkin, but the eye, nose, and mouth pieces are saved. These pieces are then gently placed back into the holes in the pumpkin.

On February 3, 2023, a train derailed in the town of East Palestine, Ohio.^1-2 Five of the train cars were carrying vinyl chloride (Figure 1), a compound that is mostly used to make PVC.

Various items (hot dogs, bananas, flowers, racquetballs, plastic cups) show properties akin to glass when chilled in liquid nitrogen.^1-4 Objects such as racquetballs and plastics behave in this manner because they are made of polymers, and polymers can become cooled below what is known as the glass transition temperature (T_g) for t

Co-Authored by Tom Kuntzleman* and Grazyna Zreda** *Spring Arbor University, MI and **Tanque Verde HS, AZ

Lightning exhibits some of the most fascinating phenomena on planet Earth.