Why Hot Water Freezes Faster Than Cold

[Jamie D]

Why Hot Water Freezes Faster Than Cold—Physicists Solve the Mpemba Effect

* Aristotle first noticed that hot water freezes faster than cold, but chemists have always struggled to explain the paradox. Until now.

Water may be one of the most abundant compounds on Earth, but it is also one of more mysterious. For example, like most liquids it becomes denser as it cools. But unlike them, it reaches a state of maximum density at 4°C and then becomes less dense before it freezes.

In solid form, it is less dense still, which is why standard ice floats on water. That's one reason why life on Earth has flourished— if ice were denser than water, lakes and oceans would freeze from the bottom up, almost certainly preventing the kind of chemistry that makes life possible.



Then there is the strange Mpemba effect, named after a Tanzanian student who discovered that a hot ice cream mix freezes faster than a cold mix in cookery classes in the early 1960s. (In fact, the effect has been noted by many scientists throughout history including Aristotle, Francis Bacon and René Descartes.)

Full article at the link

(It's all in the bonds)

[Jessica Merriman]

Can you work on this whole Gender Dysphoria thing now, please? *giggle* 

[Jamie D]

I think I would rather sit in the jacuzzi, set at about 102F.

[Miss_Bungle1991]

I think I would rather sit in the jacuzzi, set at about 102F.

OUCH!

[LordKAT]

Without reading the article, I blame Newton and his laws.

[JLT1]

And if I were to run outside right now and toss a glass full of hot water into the air it would freeze so fast there would be a loud pop.

it's cold out there

Hugs

Jen

[Jamie D]

Without reading the article, I blame Newton and his laws.

Isaac or Fig?

[LordKAT]

Fig has laws?

[peky]

Why Hot Water Freezes Faster Than Cold—Physicists Solve the Mpemba Effect

* Aristotle first noticed that hot water freezes faster than cold, but chemists have always struggled to explain the paradox. Until now.

Water may be one of the most abundant compounds on Earth, but it is also one of more mysterious. For example, like most liquids it becomes denser as it cools. But unlike them, it reaches a state of maximum density at 4°C and then becomes less dense before it freezes.

In solid form, it is less dense still, which is why standard ice floats on water. That's one reason why life on Earth has flourished— if ice were denser than water, lakes and oceans would freeze from the bottom up, almost certainly preventing the kind of chemistry that makes life possible.



Then there is the strange Mpemba effect, named after a Tanzanian student who discovered that a hot ice cream mix freezes faster than a cold mix in cookery classes in the early 1960s. (In fact, the effect has been noted by many scientists throughout history including Aristotle, Francis Bacon and René Descartes.)

Full article at the link

(It's all in the bonds)

Please note that the "manuscript" has not been published in any peer-review journal, and thus it is speculative at best

[JoanneB]

Fig has laws?

In a sense... He is a private investigator favoured by Horace Rumpole Esq.

F. I. G. "Fig" Newton (Jim Norton) (Series 3); (Frank Mills) (Series 5-6): Rumpole's favourite private investigator, who is usually battling a cold as he's often called on to tail suspects through the pouring rain. In his first appearance, when played by Norton, he introduces himself as Ferdinand Ian Gilmour Newton. All later appearances were by Mills, and in these appearances Rumpole refers to him as Ferdinand Isaac Gerald Newton.