It has been suggested for over 2,000 years that warmer water will freeze faster than colder water. Even as far back as Aristotle this was thought with the Greek philosopher stating:

"The fact that the water has previously been warmed contributes to its freezing quickly: for so it cools sooner. Hence many people, when they want to cool water quickly, begin by putting it in the sun."

A high school science teacher asked their class to help take part in an experiment to test this idea. In order to conduct the testing, they randomly allocated each student to one of two groups. The first group would test the time it takes for water to freeze when starting with hot water. The second group would time how long it takes for water to freeze when starting with cold water.

Students were each supplied with a wireless infrared thermometer in order to set the initial tem- peratures of the water to a set temperature depending on what group they were allocated to. The thermometers could also be used to measure when the water is frozen without the need to open the freezer door in their home kitchen.

Data collected for the time taken for the water to freeze in minutes is shown below:

Hot Cold 285 307 304 307 303 295 294 300 288 310 292 324 313 312 299 326 316 315 323 305