Timeline for Why don't things get destroyed by gas molecules flying around?
Current License: CC BY-SA 3.0
7 events
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| Apr 28, 2015 at 5:28 | comment | added | Artelius | Water has a high heat capacity (a lot of heat energy must be added to raise the temperature by 1 degree). All this energy must go somewhere; rather than making the water molecules fly around faster, much of it goes into overcoming the dipole forces holding the water molecules together. It is important to realise that melting and boiling points, though seemingly simple, are determined by very complex interactions at molecular scales. They are affected by simple things like molecular mass as well as complex things like crystalline structure, molecular shape, directional bonds, impurities, etc. | |
| Apr 26, 2015 at 23:37 | comment | added | HyperLuminal | So, why does water, with such a high attraction to each other, melt, when other cold things do not? | |
| Apr 26, 2015 at 8:13 | comment | added | Artelius | "if only the exterior is exposed, we should expect everything to start being worn out and destroyed around us"--I never suggested that! In fact the point of my post is that the "smashing bullets" analogy works well in certain circumstances, like when the object in question is colder than the air. I intended this to be a stepping-stone to understanding why air doesn't just turn all objects to dust. I address that in my 2nd-last paragraph. | |
| Apr 26, 2015 at 8:13 | comment | added | Artelius | "If you place an ice cube in below-freezing temperatures", then the gas molecules are still travelling very fast, but not as fast as at room temperature. At a given velocity, bullets do less damage the lighter they are, and gas molecules are VERY light. Below freezing point, the damage done is not enough to cause melting. Also note that above freezing, the temperature of the gas affects the rate of melting, so as expected the faster the "bullets" travel, the more "damage" occurs. | |
| Apr 26, 2015 at 8:12 | comment | added | Artelius | "Ice cubes melt because of the heat." Well, they melt because of heat transfer. One mechanism of heat transfer is conduction. And in the case of an ice cube (which is quite dense compared to air), conduction is quite nicely visualised as a cloud of bullets whizzing around and crashing into a wall of vibrating magnetic bricks, knocking them out of place and making them vibrate more violently until they start being able to wander well away from their original position. The birth of a liquid! | |
| Apr 24, 2015 at 12:14 | comment | added | HyperLuminal | Incorrect. Ice cubes melt because of the heat. If you place an ice cube in below freezing temperatures, it will be intact even though gas molecules still go at extremely high speeds. Plus if only the exterior is exposed, we should expect everything to start being worn out and destroyed around us according to your logic. | |
| Apr 24, 2015 at 2:40 | history | answered | Artelius | CC BY-SA 3.0 |