It brings me no pleasure to dredge up this old chestnut again. The article,
“Which freezes faster, hot water or cold water?”
was, I thought, well tackled by Cecil.
The article suggested that hot tap water takes longer to freeze than cold tap water. It also suggests that boiling water freezes more quickly, as per Scientific American column, aided by evaporation of the boiling water.
Now I hear that hot water does freeze more quickly than cold, 35C being the quickest to freeze and 5C being the slowest. It is called the Mpemba effect.
Since Cecils experiments would have used, presumably, approx. 60C and 20C water respectively, it is a wonder that he did not notice the effect.
And all this time I have been telling people that it is an old-wives tale. I have been lead astray.
Does anyone feel like designing an experiment in order to plot cooling curves down to freezing for water of a range of temperatures starting between 0C and 100C? I don’t know how thorough the original 1969 Mpepa paper was