what happens at 0 kelvin?
401975
No one has ever reached zero kelvin experimentally, so it's not possible to give a definitive answer. \nHowever, i would like to answer your question on what we believe happens at 0 kelvin.\n\nWhat happens to the atoms?\nIt is not true, as the other answers have stated, that all atomic motion stops at 0k. Recall the equation for the energy eigenvalues of a quantum harmonic oscillator as \n(n + 1/2)(Planck's Constant / 2Pi)(Angular Frequency)\nWhere n = energy level.\nNow, if we model the interatomic bonds as sort of springs between the atoms, then at 0k, we could apply the above equation, with n=0 (lowest energy state allowed for oscillator)\n\nNOTICE THAT n + 1/2 becomes 0 + 1/2 = 1/2\nI.E. THE ENERGY IS NOT ZERO AT 0K\nThere is still some energy associated with the vibration of the atoms in the potential.\nIt is only true to say that all atoms have the lowest possible vibrational energies\n\nWikipedia "Simple/Quantum Harmonic Oscillator" if you want more info.\n\nWhat happens to the electrons in the atoms? \nAt a very basic level, at 0k, the electrons all drop into the lowest energy states possible allowed by the Pauli Exclusion Principle. I.E. There is a uniform probability of distribution of finding the electrons in bound states up to a certain energy, and after this, all states above are unoccupied.\nThis 'cut-off' energy is called the Fermi Energy.\n\nWikipedia "fermi energy" or "fermi-dirac distribution" if you want more info.
811595
Add 273 to your Celsius degree to get it in Kelvins\nK = C + 273\n\nThat's because 0-degrees Celsius = 273-degrees Kelvin. \n0-degrees Kelvin = absolute zero, so you can't have negative Kelvins. \n\nHope that helps
488787
Hair will freeze at 0 grades Kelvin.\nAnd at the second question it's yes.
1014195
It varies, but on average 2.7 degrees Kelvin. This is based on the results of the COBE data.\n\nThis is, of course, assuming that you mean deep space far from any star.
791970
Use the Gay-Lussac gas law: V/T is constant. Note that T here is the temperature in Kelvin, not in Celsius. Luckily 27 C = 300 K
964851
This is an old math riddle.  Mathemeticians and physisists like to refer to absolute zero (Kelvin scale, with no negative numbers), instead of Fahrenheit or Celsius (which are relative to the freezing and boiling points of water at sea-level).  \n\nTechnically, in a relative scale it makes no sense to speak of doubling or halving the temperature.  (If it is 0 degrees (F or C), then doubling or halving would still be 0, which makes no sense.)  \n\nA less scientistic but more human approach is to postulate a base temperature that most people find comfortable.  Let's say it's 70F (21C, 294 Kelvin, 529 Rankine, 17 Reamur).  If today is "cold", it means less than 70F.  E.g., maybe today was 50F.  So it was 20 degrees (F) colder than is comfortable (70 - 50 = 20).  If tomorrow will be "twice as cold," it will be 70 - [2 x (70 - 50)] = 70 - (2 x 20) =  30F.  Quite cold!
284973
-213.8 °F (brrrr).\n\nTemperature is proportional to the kinetic energy of air molecules in motion. At absolute 0, there would be no molecular motion, which is -459.67 °F. Thus 32 °F is 491.67 °F above absoltue zero.  If the molecules have half the energy as that, I suppose it could be considered twice as cold (half as warm = twice as cold?). 491.67/2 = 245.8 °F above absolute 0 and below 32 °F. So 32 - 245.8 = -213.8 :)\n\nUsing the absolute (Kelvin) temperature scale simplifies this calculation because absolute 0 is 0 K.
830202
Depends on pressure/altitude.  At sea level its about 100C or 212F.
974506
It's absolute zero, where there is no heat, and therefore no movement of particles.  It is -273 C.
5942
It depends what degrees you're talking about. For example, if it were 0 degrees in Celsius, that's 32 degrees Farenheit, and twice as cold would logically be 16 degrees Farenheit. But 0 degrees Celsius is also 273 degrees Kelvin, and twice as cold would be 136.5 degrees Kelvin. I guess in this case, the units of measure really matter.
1107145
Temperature is indicative of the energy of a system. Ultimately temperature is a measure of the average energy of atoms or molecules of a system. The Kelvin scale is a scale that theoritically start from a state of a system with zero energy. Since energy cannot be negative (we havent observed one in nature) so consequently there is no negative temperature in degree kelvin.\n\nSo what happens really when an atom reaches the threshold of zero degree kelvin? Nobody has done an experiment that reached that temperature so far. To me I think its the opposite extreme of the big bang in the miniature scale. At the start of the big bang it was all energy, then it became cooler, some energy condensed to matter. So at zero degree kelvin, the system has no energy, I mean the system is pure matter with no internal energy.
825292
i guess I'm wrong   but I thought that water would  freeze at 0  degrees celsius.  also it would boil at 100 degrees C. Even in a vacuum.  my guess!  btw at absolute 0  kelvin,  does that only exist in a vacuum?  If we could reach  - 450 degrees F.  would our cpu's operate at an infinite speed.....got me on this one.  I'm not sure on how atmospheric pressure relates to these conditions.  But I know someone knows!
605145
no...it cant get colder than absolute zero....thats why its called absolute....molecules dont move forward or backward ....you should think of them as energy particles....electrons dont really move around a nucleus either....dont think of them as planets around the sun they are more like energy fields.  the more negative the charge the more "electrons"....if there is any movement....even if it were possible to move backwards it would be warmer....movement causes friction and, therefore, heat.  it you cant get less than nothing.
1026360
in theory, when the temp reaches absolute zero everything freezes and is -459.67 degrees F.  temps within a few billionths of a degree have been reached but the materials used in the experiment took on nontraditional states.  at the temp all molecular motion would cease so it would be impossible to reach the temp exactly.
32289
One answer would be to convert 0C into 273 Kelvin or 32 F and then do some multiplication.\n\nBut "cold" is really a subjective measure based on physiology. I suspect if you did a test with actual humans you would find that around -10.6 C feels twice as cold as 0 C.\n\nThat is what this wind chill calculator finds, if wind speed is always zero.
799142
Hi Kitty,\nHere is what, I think, you need.\n\nExothermic, dH < 0, Entropy increases (dS > 0), Reaction is spontaneous and dG < 0\n\nExothermic, dH < 0, Entropy decreases (dS < 0), Reaction is spontaneous only at low temps, if |T dS| < |dH|\n\nEndothermic, dH > 0, Entropy increases (dS > 0), Reaction is spontaneous only  at high temps, if T dS > dH\n\nEndothermic, dH > 0, Entropy decreases (dS < 0), Reaction is not spontaneous, dG > 0
1173163
Anyone thinking that hasn't spent any time at my place.\n\nAbsolute Zero is how cold it is when hydrogen atoms stop moving.\n\nAnything colder than that is the area in and around my bed immediately after I ask my wife for sex.