Does hot water freeze faster than cold water?

Photo credit: Henry McIntosh/Unsplash

This question has been the basis of many a year 10 SRP and has baffled scientists for years. The Mpemba effect, which is often cited as an explanation is really more of an observation. Now a number of teams have published work investigating the Mpemba effect. Read more here:

Mexican scientist invents glow-in-the-dark cement

Glow in the dark cement

It’s taken nine years of work, but it turns out it can be done. Scientist Jose Carlos Rubio, of Mexico’s University of San Nicolas de Hidalgo, has just patented his glow-in-the-dark cement. And what are its applications, other than looking very cool? Dr Rubio believes it could be a new way to light cities, streets and buildings without using electricity: the only thing emitted during its production is water vapour. It was a long process. Part of the challenge was cement’s opacity: the trick, he discovered, was to remove the crystal flakes that occur as a by product in one production method, which is done by changing the microstructure of the cement. for full article



Chemiluminescence is the technical term given when a chemical reaction gives off light!

In year 8 we study the ‘signs that a chemical reaction has taken place’. One of the signs that a chemical reaction has occurred is that it gives off energy – typically this energy is in the form of heat, but in a few cases the energy given off can be light! Different colours are made by different amounts of energy.

Check out these chemiluminescent reactions that our science club team recently experimented with:

Just in case it’s not obvious – don’t try this at home! See here for more details about why and the details behind how glow sticks work.