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/ck/ - Food & Cooking

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9554691 No.9554691 [Reply] [Original]

is it true hot water freezes faster

>> No.9554703

In some contexts yes

>> No.9554716

Based on thermal dynamics this seems like the exact opposite of things which would happen

>> No.9554721

Yea.

>> No.9554737

>>9554691
Only if the top is off and it can evaporate.

>> No.9555002

Yes

>> No.9555025

I just put boiling water in the freezer and a bottle of water from the fridge in the freezer. What I learned is not to put boiling water in the freezer.

>> No.9555072

>>9554703
Like Schrodinger's ice cubes?

>> No.9555130

Better question is: How do you get your cubes out the tray without cracking the plastic?

>> No.9555172

>>9554691
Just pre freeze your trays

>> No.9555177

>>9555130
Gently twist until they pop loose. Then dip your fingers in some water and pluck them out.

>> No.9555184

>>9555130
Use a tray made of ice instead of water

>> No.9555186

>>9555025
Why?

>> No.9555190

>>9555130
Just tap it on the counter?

>> No.9555194
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9555194

>>9555184
>water trays freeze ice

>> No.9555212

>>9554691
no

>> No.9555219

>>9555130
Don't over fill your tray.

>> No.9555220

its possible but no one can really do it consistently.

either way its not that much faster so you would probably lose time if you waited for water to get hot anyways

>> No.9555228

hot water's rate of freezing is faster but since it's hot it's still going to take longer to freeze than cold water so it's pointless

>> No.9555230

>>9555186
Long story short, I got kicked out of Gregg's

>> No.9555241

No, but as I recall that's how you get clear, air-free ice cubes

>> No.9555259

>>9555230
tell us what happened lad

>> No.9555260

>>9554691

It freezes faster than hotter water.

>> No.9555268

>>9555259
Well I got kicked out of Gregg's for being racist

>> No.9555277

>>9555241
That's boiling water and letting it cool; but distilled water produces the same if not more clear ice.

>> No.9555313

>>9554691
This was actually a science experiment we did back in elementary school. The most common hypothesis was that the cold water would freeze quicker.

It didn't. Weirdly enough, the boiling water froze first. Same exact conditions, just one was boiling water.

>> No.9555333

>>9555268
Did you tell England is God's country.

>> No.9555551

>>9555130
Dip the bottom of the ice cube tray in warm water. I've found that shitty old trays that won't let the cubes go either have a rough surface from plastic degradation or have a crust of mineral scale built up on them. Try to clean them or just get new trays. They're not expensive.

>> No.9555605

Lmao how could hot water freeze faster? Dumbasses.

>> No.9555620

>>9555130
use an ice machine

>> No.9555652

https://en.wikipedia.org/wiki/Mpemba_effect
Whoa. This shit is fascinating. Completely contrary to what one would logically assume and scientists don't even know why it happens.

>> No.9555686

My grandpa used to say that thinking hot water froze faster than cold water was something only someone from Cincinnati would be dumb enough to believe but now it looks like Im learning all sorts of things

>> No.9555697

>>9555130
grab the ends of the tray at opposite corners and twist

>> No.9555699

>>9555686
I can see why he'd say that. One would logically assume it'd take longer to freeze hot water than cold as the hot water would need to lose more energy to freeze, but it seems as if hot water loses energy more quickly for some reason and, bizarrely, continues losing energy at a faster pace even once it reaches the same temperature as the cold water.

>> No.9555766

Is the reason why it freezes faster because the hot water molecules are spazzing autistically making it easier to change states?

>> No.9555916

the difference in freezing rates is negligible really. the only real advantage in freezing boiling water is for clarification purposes. it creates more solid uniform solid blocks perfect for chipping for cocktails etc

>> No.9555921

>>9555130
I have an ice tray that has a silicone bottom, and when you press on it, the ice cube just pops out. Maybe look for something like that if you want a more convenient tray.

>> No.9555947

>>9554691
Think for one minute about what you just said
>will a portion of water further from the freezing point than another portion of water have its average temperature fall below the freezing point first?

>> No.9555950

>>9555947
Except it happens tard.

>> No.9555952

>>9555313
Boiling water removes air, which interferes with the bonding.

>> No.9555955

>>9555950
Boiling and "hot" are different.

>> No.9555956

>>9555950
Boiling water = more evaporation = less water to freeze.

>> No.9556000

from what i heard its inconclusive. replicable, but not consistant.

>> No.9556022

https://en.wikipedia.org/wiki/Mpemba_effect

>> No.9556025

>>9555333
nice digits

>> No.9556064

>>9555652
>>9556022
it's almost like simple questions can be googled rather than having a thread dedicated to them

>> No.9556077

>>9555130
why are you buying cheap shitter planned obsolescence trays that crack easily? are you american or something?

>> No.9556084

>>9555268
You got kicked out?

>> No.9556129

>>9555220
>but no one can really do it consistently.
they do, though.

>> No.9556133

>>9555956
Dang /ck/ is really a new level of fucking dumbasses

>> No.9556140

>>9556133
yeah, like, people keep professing their opinion without doing any research on what they're talking about

>> No.9556158

>>9555130
put it in the microwave, that way you can easily pour out the cubes

>> No.9556173

>>9555652
>In 2012, the Royal Society of Chemistry held a competition calling for papers offering explanations to the Mpemba effect.[19] More than 22,000 people entered and Erasto Mpemba himself announced Nikola Bregović as the winner. Bregović suggests two reasons for the effect a colder sample gets supercooled rather than frozen, and enhanced convection in the warmer sample speeds up cooling by maintaining the heat gradient on the container walls.[20]

I can't even begin to make sense of the other explanation.

>> No.9556655

>>9555130
use a rubber tray

>> No.9556660

>>9554691
https://en.wikipedia.org/wiki/Mpemba_effect

>> No.9556680

>>9555555

>> No.9556982

>>9556173
The rate at which heat is transferred between two objects depends on the temperature difference to the fourth power, a very dramatic effect. If you have warmer water it will generate a convection cell, meaning better mixing of water, so as the outside cools, it gets replaced with warmer water. This maintains a large gradient and thus the rate of cooling is higher. I don't know if this is exactly how it works in reality but that's what the theory is trying to convey.

>> No.9557340

>>9554691
No it wont freeze faster. People who think this are utterly retarded and don't think. At some point the water that's warmer before reaching freezing will be the same temperature as the cooler water freezing slower. So now you have 2 cold waters and one is supposed to freeze faster how?

>> No.9557342

>>9557340
Why are you bringing logic and reason into what is obviously a shitposting thread?

>> No.9557357

>>9556982
>This maintains a large gradient and thus the rate of cooling is higher.
Right. But once you get to the point that the "hot water" has cooled down to level of cold water you're at the exact same point but you've already had to waste time to get there.

>> No.9557437

>>9556064
this is a thinking mans thread. If you want to whine rather than think, please leave.

>> No.9557450

>>9555699
Two possible reasons: lack of atmosphere dissolved in the water, allowing for the bonds to happen faster. Or the evaporation process, which helps to cool the water by removing overly excited molecules as well as pull in cold air to dissolve in the water to take the place of the missing mass.

>> No.9557474

>>9557357
You're thinking about it in terms of acceleration when you need to go past that and examine the jerk, the rate of acceleration. The acceleration of the hotter water to a freezing point will, at it's initial stages, occur faster than the acceleration of colder water to the freezing point. Thus, the rate of acceleration will be faster in the hotter water, and it will decelerate slower. So yes, the two waters will get to the same point, and it will take the hotter water longer to get there, but at the point the hotter water will be accelerating to ice faster than the colder water, so it's not hard to believe that if certain conditions are met perfectly enough, the hotter water will freeze faster.

>> No.9557488

>>9557357
You (and >>9557340) are assuming that the rate at which the (initially) hot water is cooling is the same when they have the same surface temperature. This is only the case when the water's temperature is uniform, but it's not, like >>9556982 is saying. Just because they have the same surface temperature doesn't mean the rate of cooling is the same.

Put it this way: you have two men running the 100m sprint, one at 0m and the other getting a 10m headstart. Your argument is akin to saying "well, the man will have to waste time to get to the 10 m point while the other man will have already moved on", ignoring that if the originally lagging man has a greater average velocity he will finish first.

>> No.9557515

>>9557474
>but at the point the hotter water will be accelerating to ice faster than the colder water
No. That's just complete nonsense.
Once the reach the same temperature they are cooling at the exact same rate. Heat transfer is based on Delta-T. This concept of "the jerk" is nonsense.

>>9557488
Your example works when the two men have different running speeds. But in this case there is no difference. Once the hot water gets to the point of the cold water the cooling rates are now identical in both cases, the only difference is that the hot water has to "run farther" to get to the freezing point.

If you wanted to make this a running example:
Runner A gets a 10m head start. Runner B runs faster than Runner A for his first 10 M, but once he hits the 10M mark he runs the same speed as Runner A.

>> No.9557522

>>9556064
This is a great discussion, though.

>> No.9557551

>>9557515
>Your example works when the two men have different running speeds. But in this case there is no difference. Once the hot water gets to the point of the cold water the cooling rates are now identical in both cases
They're not. Please reread>>9556982.

>> No.9557624

>>9557551
I did read it. I reject it. Do you really think there will be an appreciable "convection cell" in something as small as an ice cube tray? Not to mention the fact that convection implies the water is moving around. Moving = mixing. Even if such a cell were to start it will soon come to equilibrium and cease functioning. You need a very strong, sustained, temperature differential to create a convection cell. Sure, you can make it happen in a purpose-designed vessel equipped with strategically placed heating and cooling units but that simply isn't going to happen in the case of a warm-water filled ice cube tray stuck in the freezer.

>> No.9557689

It's almost a complete myth.

Hot water will not freeze father than cold water. The reason this belief is widespread is because the original experiment made for a good feel good story; an African kid made an amazing discovery that turns science on its head. The experiment has never been replicated, because of the feel good story, it's only recently that someone went to exhaustive efforts to try and prove the experiment and when it was, it was found to be complete bullshit.

Extremely hot water will freeze faster than not-quite-as-extremely hot water but that's because of quirks about boiling water. That wasn't what was said in the original experiment though, either the readings were faked or the experiment was carried out in a shit way.