why does ice melt at room temperature?
111129
It will only melt if room temp. is 33 degrees or higher.
1083390
The water around an iceberg or floe becomes colder than freezing (like putting ice cubes in a drink), but won't turn to ice since it is salty.  And waters in the polar regions are down near freezing to begin with.  When the berg gets sunlight some of the surface will melt off.  When the berg finally drifts to warmer waters, it will melt until it is gone.\n\nFor an example: Take a sink and fill it with water.  Put in some rock salts and stir until dissolved.  Now put in several trays' worth of ice cubes.  Stir.  Some of the cubes will melt since the tap water was not freezing, but eventually the sink water will get to a temperature below 32 degrees F or 0 degrees C without freezing solid.  At that point the coldness of the water keeps the remaining ice cubes frozen and the ice cubes keep the water at a below freezing temp.  Eventually it will melt cause there will be heat absorption into the system raising the water temperature, but it will take awhile.
749533
All atoms have intermolecular forces that keep them together as solids or liquids. Adding energy will overcome these forces and cause them to change phase from solid->liquid->gas (with a few that jump straight from solid to gas).\n\nEnergy has to be added to cause this phase change. Going in the opposite direction requires withdrawing energy.\n\nThe types of forces or bonds (not chemical bonds) absorb energy when broken, give up energy when formed. It implies that the solids are in a lower energy state than liquids, and liquids lower than gases.\n\nThis said, when water turns in ice, heat energy is being withdrawn, and the molecules are getting into a more stable and fixed configuration with respect to each other. Because of the polar nature of water, it forms hydrogen bonds between molecules. These type of bonding means when water turns into ice, it positions the molecules into very specific configurations, to maintain the lowest energy state it can get to. Hence the formation of ice crystals.
623583
answer can be a or c, but i'd go with answer c.\n\nthe melting point (which solid becomes liquid) varies by each molecules & substances.  What happen is when temp. rises, it translates into more energy put into the soild or heat absored by the solid.\n\nHowever, you can melt solid by chaning pressure, and leaving temp constant.\n\nSo best answer would be C, by heat absorption.
771899
When a solid is heated, the molecules become active and the bonds between them come looser, this is how a solid becomes a liquid.\nThe warmer the liquid becomes, the molecular bonds become even less connected and the liquid becomes a gas. (evaporation)\n\nWhen a gas is cooled, the molecular bonds change and they become tighter. or closer together causing the gas to turn back into a liquid (condensation).  And as the molecules become tighter still, then the liquid turns back into a solid.\n\nFreezing and melting points change per molecule.
454982
A crystal shape is the arrangement of the molecules in a compound...carbon fiber is a crystalline structure since it is arranged in a pattern when observed under a microscope. Glass, however isn't a crystalline structure, and will be disorganized. Also, a quick fact is that glass will always be in motion due to it's non-crystalline structure. The bottom of a pane of glass will be thicker than the top after many years :) A high melting point means that it will take more heat to induce a state change... Metal is frozen at room temperature and has a high melting point, as opposed to water, which has a melting point around 33 degrees farenheit.
377330
Salt, NaCl, turns into Na+ and Cl- ions in water.\n\nThe ions changes the equilbrium of H2O melting and freezing.\nLiquid water is block by the ions, so it has a harder time freezing back onto the ice. Since the ions doenst slow down\nthe melting of ice, but slows down the freeze of water.\nThe ice now melts at below 0 degree.\n\nSo a normal ice water will be at zero degree.\nBut a salt put on the ice/water will melt more of the ice at a lower temp., about 7-10 degree colder, depenting on the ammount of salt and ice avalibale.
625534
Everything goes from solid to whatever else one molecule at a time. It's just that under certain conditions, there is a spread between the energy that it takes to get away from the solid and the energy that it takes to exist as a gas. So, when you melt ice under one set of conditions, the molecules only have enough energy to break free from the ice crystals and go into solution. But, if the pressure is very low (outer space say) then that same amount of energy is enough to drive the water molecules into the gaseous phase instead.
807251
dry ice\nRegular ice is water and melts at room temperature\nDry ice is carbon dioxide. it sublimated at room temperature
119086
The molecules of water are closer together and constantly moving, whereas the molecules of ice are in a crystal lattice, meaning they're in a rigid formation. When water freezes, the molecules spread out a little more to form the crystal lattice. Since density is mass over volume, and ice has takes up more volume than water, the density of ice is lesser than that of water. Which makes ice float on water.
762753
The interactions between the carbon dioxide molecules are stronger, and thus it forms a solid at a higher temperature.\n\nIn water, the attractions are even stronger and you only need to go to zero degrees to get a solid. If you go to 100 degrees water becomes a gas. (temperatures in celcius)\n\nSimilarly for other molecules, if the atrraction between them is strong you get solids and liquids at higher temperatures than for less cohesive molecules.
116361
It depends on the temperature at which you are talking about. At room temp glass is a solid. However, at a high enough temperature, glass can be in liquid form, much the same way that ice melts into liquid. It just takes a lot more heat. To clarify from one of the other responses, it is liquid as long as it is in it's liquid phase. Steel is still called steel, even when it is molten enough that it's flow properties are similar to that of water. However, as we interact with steel and glass it is in it's solid phase.
247971
From what I was TOLD,\nGlass doesn't have an observable melting point. If you've seen a graph of temperature of a substance plotted against the time it is heated constantly, you'd know what 'observable' means. A substance (e.g. water) may STAY at two temperatures (0C & 100C for water) for some time even though it never stops being heated. For water the lower temperature is when ice melts and the higher when water boils, and they are called melting/boiling points respectively.\n\nDuring the time 'solid' glass is heated till it is clearly liquid, no such temperature-halt is observed, so they say glass has no observable melting point.\n\n[edit] I too prefer the way calling glass a liquid. Since it's already concisely mentioned, I added quotation marks around the word 'solid', intending to express glass appears to be solid but it may well be an extremely thick liquid.
220158
Do not offer bribes, this is immoral.\nMany here come to assist as a service.\n\nYour answer is here:\n\nWhen ice melts, kinetic energy of H2O molecules is increased by absorption of heat energy from the surroundings.\n\nHowever as the kinetic energy is increased to make the molecules move freely, Hydrogen Bonding among the water molecules becomes more effective and so a particular intermolecular distance is maintained among the molecules. \n\nThis is effective upto 4C.\n\nAfter 4C the H-bonding becomes so week as against kinetic energy that free movement of molecules is no more restricted and thus abnormal behaviour of water molecules is stopped.
189354
I discussed this experiment with some of my colleagues and we think that the CO2 (carbon dioxide) causes a stirring effect which distributes the temperature more evenly in the soda. The ice cubes serve as nucleation sites for the bubbles (a place for bubbles to grow). As the bubbles grow and then release they cause the ice cubes to circulate in the liquid. This circulation causes the warmer layer below the ice to mix with the colder upper layer of soda and ice. Have you ever noticed that when you use a straw to drink a liquid that the liquid at at the bottom of the cup is warm and requires a stir to evenly distibute the cooling? The "still" beverages (water and tea have no bubbles) will have a cold layer on top next to the ice and a warmer layer on the bottom. This would cause the ice to melt slower.\n\nHere is an experiment to try. Allow some soda to get flat overnite, then try the experiment again.\n\nKeep in mind that temperature is the average kinetic energy of the particles in a substance, whereas heat is the total energy of all the particles. The air and water may have particles moving the same speeds, but the water has more heat because there are more particles. \n\nPicture it this way. The ice melts as fast moving particles slam into the slow moving ice particles. As in any collision, some of the energy is transferred to the ice particle, and with its new energy it can break out of the crystal and flow as a liquid water molecule. \n\nTo make the ice melt faster, you can use hotter (faster moving) particles to slam into it. This is why the ice melts faster on a hot day than a cold one. Alternatively, you can just use more collisions. The water is much more dense than the air, with many more particles per cubic millimeter. Thus even though the water molecules have the same kinetic energy as the air particles, there are many more of them hitting the ice each second, and the ice melts faster.
86483
Actually, Gonpatrick, the original question is quite correct: Unlike most substances, water does actually expand when it is cooled, over a narrow temperature range from about 4 degrees C to 0 degrees C (the freezing point.)  This is why water freezes from the top down: the cooler water that is closer to freezing is less dense than, and so floats above, slightly warmer water.  (Above 4 degrees C, water expands when it is heated just like most other substances.) When the water freezes it expands some more, which is why ice floats.\n\nThe reason why it does this has to do with the way water molecules are put together.  The two hydrogens and one oxygen in H2O are assembled in a triangular pattern, with one part of the molecule more positive and the other more negative.  Above 4 degrees C, the molecules move freely around each other, but when it gets close to its freezing temp, the molecules start to align themselves with the positive part of one molecule near the negative part of another, ultimately forming, when it freezes, a hexagonal pattern.  This arrangement takes up more room than when the molecules are free to move around.
694958
Under normal curcumstances when water is cooled, it will form ice at its freezing point.  That is crystallisation takes place and an ice cube is formed.  If now the liquid is cooled past its freezing point without crystallisation taking place, a glassy substance is formed.\n\nWe can also cool saturated solution, without crystalllisation taking place to form a super saturated solution.  This is super cooling.