Fun Science Facts

orangeblooded2

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It's the Mpemba effect. We say "Not always" because science has no damn clue why it happens or what the parameters are, just like how water actually expands when it freezes instead of getting smaller like most things do.

My textbook explains it like this

There exists a set of initial parameters, and a pair of temperatures, such that given two bodies of water identical in these parameters, and differing only in initial uniform temperatures, the hot one will freeze sooner


I've always thought of it like this. Like an engine burning fuel \ transforming matter. That once that motor has started the more energy in the start up the quicker more efficient it runs \ drives\ transforms. If you can picture what I've trying to convey.
 

Daloth

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I've always thought of it like this. Like an engine burning fuel \ transforming matter. That once that motor has started the more energy in the start up the quicker more efficient it runs \ drives\ transforms. If you can picture what I've trying to convey.
I get what you mean and I see it the same way really, especially when you think about how heat rises and that a greater temperature/pressure difference leads to a higher rate of change/diffusion, so you really have three (or possibly more, since we don't understand water at all really) different systems working on it to freeze.
 

volfan_89

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It's the Mpemba effect. We say "Not always" because science has no damn clue why it happens or what the parameters are, just like how water actually expands when it freezes instead of getting smaller like most things do.

My textbook explains it like this

There exists a set of initial parameters, and a pair of temperatures, such that given two bodies of water identical in these parameters, and differing only in initial uniform temperatures, the hot one will freeze sooner
I don't know all the details but there also a way to instantly freeze a coke under the right circumstances. I'm on mobile or I would post a video. YouTube it if interested. Pretty interesting stuff.
 
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I've always thought of it like this. Like an engine burning fuel \ transforming matter. That once that motor has started the more energy in the start up the quicker more efficient it runs \ drives\ transforms. If you can picture what I've trying to convey.
When I was in high school, I used to make the argument of thermal inertia (which does somewhat exist to the eye but really isn't inertia I suppose) as being responsible for the water phenomenon. I think this is somewhat related to your more energy more efficiency argument but not exactly.

However, most liquids don't behave in this way. Hot ethanol will not freeze faster than cold ethanol, for example. So it seems that it is likely a consequence of the unique hydrogen bonding characteristics if water, which other liquids don't match to the same degree.

The unique hydrogen bonding behaviors of water and it's molecular shape also give rise to its expansion upon freezing.
 

orangeblooded2

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When I was in high school, I used to make the argument of thermal inertia (which does somewhat exist to the eye but really isn't inertia I suppose) as being responsible for the water phenomenon. I think this is somewhat related to your more energy more efficiency argument but not exactly.

However, most liquids don't behave in this way. Hot ethanol will not freeze faster than cold ethanol, for example. So it seems that it is likely a consequence of the unique hydrogen bonding characteristics if water, which other liquids don't match to the same degree.

The unique hydrogen bonding behaviors of water and it's molecular shape also give rise to its expansion upon freezing.



Hydrogen bonding.

If i remember right thats surface tension with oxygen getting the most of the excited electrons? I'm hoping this is right and a very old memory serves.
 

Thrasher865

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When I was in high school, I used to make the argument of thermal inertia (which does somewhat exist to the eye but really isn't inertia I suppose) as being responsible for the water phenomenon. I think this is somewhat related to your more energy more efficiency argument but not exactly.

However, most liquids don't behave in this way. Hot ethanol will not freeze faster than cold ethanol, for example. So it seems that it is likely a consequence of the unique hydrogen bonding characteristics if water, which other liquids don't match to the same degree.

The unique hydrogen bonding behaviors of water and it's molecular shape also give rise to its expansion upon freezing.
If this "thermal inertia" were a thing, it would cancel out, much like the forces involved in a pendulum.
 
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Hydrogen bonding.

If i remember right thats surface tension with oxygen getting the most of the excited electrons? I'm hoping this is right and a very old memory serves.
Basically hydrogen will share electrons with two oxygen atoms. The one it is covalent key bonded to and another that it is bonded to through hydrogen bonding. I wouldn't say it is surface tension, but hydrogen bonding might give rise to water's high surface tension...not sure about that.
 

Orangedogsrule

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If aliens 65 million light years away were looking at us through a telescope, they'd be seeing Dinosaurs.
Strange how that's true. But only when we think about it. And we can sweep through 100 million, a billion, 14 billion years of the universe in our minds. But when we go outside and look at their star where their planet is, it is we who are seeing their Dinosaurs.
 

BEATBAMA12

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We got my son a butterfly kit, it came with 6 "painted lady" butterfly caterpillars, and a round net like structure, after they metamorphosed into butterflyies there was a lot of blood all over the bottom of their house, they stink and are really messy, get them for your kids if you like but it's a mess!
 

creekerballer

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Flatworms have both male and female reproductive organs. During mating they engage in a match of penis fencing which can last up to an hour, one flatworm will stab and inseminate the other who then becomes pregnant.
 

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