Which takes longer, to cool down or to warm up?

[Moh]

If there was some water, one boiling and one freezing (say equal distance from room temperature) - which one would hit room temperature first?

Google was useless :P

[Recursion]

I'm guessing it would depend on the container the water was in, the surface area of the water, but I would think boiling water would cool faster than the freezing would warm due to to convection

[Apple]

You have made it confusing. Freezing water is 0 degrees, boiling water is 100 degrees. If room temp is 21 degrees that means the frozen water (ice) only has to heat up by 21 degrees but the boiling water has to cool down by 69 degrees. I also googled it but couldn't find much. :P

[Recursion]

You have made it confusing. Freezing water is 0 degrees, boiling water is 100 degrees. If room temp is 21 degrees that means the frozen water (ice) only has to heat up by 21 degrees but the boiling water has to cool down by 69 degrees. I also googled it but couldn't find much. :P

"one boiling and one freezing (say equal distance from room temperature)" :P

Water can still be frozen at say -70c though, so it does make sense.

[Conservative,]

I'd say boiling - the water looses heat faster than it gains it. Can't really explain it but it makes sense to me haha.

[Moh]

Would heat flow be the same, hot or cold?

[Stephen]

doesn't hot water freeze faster than cold water

[kuzkasate]

I think it takes longer to warm up tbh
I remember doing something about it

[Apple]

I doubt you are ever going to find a valid answer but I would of thought that it takes longer to warm up.

[Ardemax]

deffo depends on the temperature of each liquid and i think it's the colder one that loses it's like coldness first? dont trust me 100% on it

[Casanova]

i'm sure it's quicker to freeze than to boil. Especially with flash freezing (a phenomenon where water get's to down to -21c and then when you disturb the water it instantly freezes in front of your eyes).

[Boonzeet]

If room temperature is 21ºC; and you have two cups of water - one at 0ºC (frozen) and one at 42ºC (equidistant from room temperate);

The cup that is at 42ºC will cool down faster than the cup at 0º for various reasons. Namely, the frozen water has no convection as it is a solid, it also has to change state from a solid to a liquid which requires a higher energy curve.

---------- Post added 26-10-2010 at 04:48 AM ----------


i'm sure it's quicker to freeze than to boil. Especially with flash freezing (a phenomenon where water get's to down to -21c and then when you disturb the water it instantly freezes in front of your eyes).

temperature change required to boil water from room temperature - 79º
temperature change required to freeze water from room temperature - -21º

it seems fairly likely that its easier to freeze.

but a more obvious factor - if its a really hot substance heating up the water (kettle) and a not-very-cold setting cooling it down, like only -1º, it'll heat up a lot faster.

there are so many variables to this question it cant even be considered.

[Richie]

to warm up.. trying to cool down is so much harder because if your brains saying your hot your still gonna sweat like mad. Just flick on the radiators and throw a blanket over you.