Most recent answer: 10/22/2007
And water freezes at 32 degrees Fahrenheit. But it can actually get colder than that, all the way toward what we call absolute zero. This value is equivalent to about -459 degrees Fahrenheit. This is when the water molecules are basically not moving. Hope this answers your question!
(but see below- if the question concerns liquid water, it becomes unstable outside the temperature range mentioned, at atmospheric pressure. Mike W.)
(published on 10/22/2007)
Follow-Up #1: boiling and superheating
If the temperature is much above 212°F, the water will boil. That means that it won’t just evaporate from the surface but will form vapor bubbles, which then grow, inside the liquid itself. If the water has very few dust flecks etc. in it, this boiling process doesn’t happen until the temperature is significantly above 212°F, so you can temporarily have liquid water (called ’superheated’) above that boiling point. If there are good nucleation sites for the boiling to start (teflon surfaces are a good example) you can’t get much superheating.
you might search this site and others using the key word ’superheated’.
(published on 10/22/2007)
Follow-Up #2: superheating?
- Andy (age 68)
SLC, UT, USA
The water can be somewhat superheated, as we mentioned. Also, by the time the water is boiling the pot will be hotter than 212°F, so heat from it flows in to boil some more water.
(published on 04/17/2017)
Follow-Up #3: water at 6500 °F?
- Craig Godfrey (age 33)
I have no idea how liquid water could exist at that temperature. It's far above the "critical point" at which the distinction between gas and liquid is lost. I'm pretty sure that at that high temperature water molecules mostly fall apart, so you really wouldn't have water at all.
(published on 08/29/2017)
Follow-Up #4: water at 212°F
- Kyah (age 10)
(published on 11/01/2017)
Follow-Up #5: temperature of ice and water
- Natasha R. (age 17)
Ice can certainly be much colder than 0°C. Even liquid water can be a bit colder than 0°C for a while, until it manages to find its way to the crystalline ice state. We discuss that a lot on this site under the name "supercool".
Usually when you stick the water in the cold freezer it will cool just a little past 0°C, then hang up near 0°C until all the water has turned to ice, then continue cooling until it reaches the freezer temperature. If the water is unusually free of dust, etc. it may supercool pretty far below 0°C before the freezing starts.
(published on 01/29/2018)
Follow-Up #6: vapor pressure
- Eli Tatum (age 19)
Even below 100°C, some water molecules will escape from the liquid and go into the vapor. Equilibrium is reached when their concentration (the density of the water vapor) is high enough so that the rate of molecules coming back from the vapor and rejoining the liquid just balances the rate at which they leave. These molecules in the vapor are truly in the gas phase, not contacting each other much.
So what's different at 100°C? Above 100°C the molecules leave the liquid so fast that equilibrium could only be reached with water vapor so dense that its pressure would be higher than ordinary atmospheric pressure. So at atmospheric pressure, all the water molecules leave the liquid and join the gas. Below 100°C, only some do, at least in a closed container.
(published on 06/14/2018)