When we discussed energy transformations last semester, we talked about energy losses. What is energy usually transformed into when it is lost? How would you describe these losses in terms of thermodynamics? Why do I have losses and lost in quotation marks? Describe the Second Law of Thermodynamics using direction of heat flow, entropy, and/or probable states. If a hot brick is next to a cold brick, heat flows from the hot brick to the cold brick until both bricks arrive at thermal equilibrium. If the hot brick takes heat from the cold brick and becomes hotter, the first law of thermodynamics is not violated. However, this would violate the second law of thermodynamics. The second law of thermodynamics describes the direction of heat flow in natural processes. Heat flows one way, from hot to cold. In winter, heat flows from inside a warm heated home to the cold air outside. In summer, heat flows from the hot air outside into the homes cooler interior. Heat can be made to flow the other way, but only by imposing external effortas occurs with heat pumps. There is a huge amount of internal energy in the ocean. All this energy cannot be used to light a single flashlight lamp without external effort. Energy will not of itself flow from the lower- temperature ocean to the higher-temperature lamp filament. The first law of thermodynamics states that energy can be neither created nor destroyed. The second law adds that whenever energy transforms, some of it degenerates into waste heat, unavailable to do work. Another way to say this is that organized, usable energy degenerates into disorganized, nonusable energy. It is then unavailable for doing the same work again. Push a heavy crate across a rough floor and all your work will go into heating the floor and crate. Work against friction turns into disorganized energy. Organized energy in the form of electricity that goes into electric lights in homes and office buildings degenerates to thermal energy. The electrical energy in the lamps, even the part that briefly exists in the form of light, turns into thermal energy. This energy is degenerated and has no further use. The Transamerica Pyramid and some other buildings are heated by electric lighting, which is why the lights are on most of the time. We see that the usefulness of energy is lowered with each transformation. Organized energy tends to transform to disorganized forms. Imagine that in a corner of a room sits a closed jar filled with argon gas atoms. When the lid is removed, the argon atoms move in haphazard directions, eventually mixing with the air molecules in the room. The argon atoms do not spontaneously move back into the jar to return to the more ordered containment. With the number of ways the argon atoms can randomly move, the chance of returning to an ordered state is practically zero. Why does your bedroom tend to get messier over time? Is it possible that a tornado would pass through a lumber yard and construct a wooden building? Disordered energy can be changed to ordered energy only at the expense of work input. Plants can assemble sugar molecules from less organized carbon dioxide and water molecules only by using energy from sunlight. In the broadest sense, the message of the second law is that the tendency of the universe, and all that is in it, tends to disorder. Complicated, organized things are highly ordered. A mechanical watch will only function correctly if all the little gears and springs are in just the right places. An organism continues to live only if billions of organelles and cells are in the right place, functioning correctly. The first law of thermodynamics is a universal law of nature for which no exceptions have been observed. The second law, however, is a probability statement. Disordered states are much more probable than ordered states. Even the most improbable states may occur, and entropy spontaneously decrease: haphazard motions of air molecules could momentarily become harmonious in a corner of the room a barrel of pennies dumped on the floor could show all heads a breeze might come into a messy room and make it organized The odds of these things occurring are infinitesimally small. The 2 nd Law can be described three ways: Heat flows naturally from areas of high temperature to areas of low temperature. Systems tend to become more and more disordered over time. Systems tend toward more probable states. Define entropy as a quantity that measures disorder of a system. Entropy is the measure of the amount of disorder in a system. Disorder increases; entropy increases. This run-down house demonstrates entropy. Without continual maintenance, the house will eventually fall apart. Entropy is low for complicated, organized systems. Entropy normally increases in physical systems. However, when there is work input, as in living organisms, entropy decreases. All living things extract energy from their surroundings and use it to increase their own organization. This order is maintained by increasing entropy elsewhere. According to the 2 nd Law of Thermodynamics, the entropy of the universe is always increasing. Even if entropy is temporarily decreased in some small system by doing work, that work causes a larger increase in entropy outside the system. So, the entropy of the universe increases. The laws of thermodynamics are sometimes put this way: You cant win (because you cant get any more energy out of a system than you put in). You cant break even (because you cant even get as much useful energy out as you put in). You cant get out of the game (entropy in the universe is always increasing no matter how much work you do). Instructions on each table. DO NOT write on the activity sheets; write all answers in your notebooks, including the checker diagrams. Table 1 Table 4 BrittneyC.Ortiz StephanieAgnes Table 7 JinheeSam Adam Table 2 JeremyC.Deng MaxChristine Table 5 TiffanySavanna Mary Table 8 Ryan Yuta Natalie Table 3 JennyWannie VivianKomal Table 6 ChianneShannon Shane Table 9 AnhGeshni Ella Table 1 Table 4 SourbhRyann Joanna Table 7 ChristineJared Chenaun Table 2 BrittneyAmy Harshpreet Table 5 Cristian Adrian Stephanie Table 8 Janet Kaylyn Nadia Table 3 JimAngelica Alex Table 6 Justin Brittny Kelly Table 9 KevinAlejandra Jake Table 1 Table 4 KarenMarina Saarah Table 7 NoahKendal Connie Table 2 BrianGreg JayJon Table 5 NikkiDan Kate Table 8 Tyler Nick Alex Table 3 CodyBen CalvinKayla Table 6 NoorKim Allan Table 9 The lowest possible temperature is absolute zero, at A. 0 on the Kelvin scale and 0 degrees on the Celsius scale. B. 0 on the Kelvin scale and -100 degrees on the Celsius scale. C. 0 on the Kelvin scale and -273 degrees on the Celsius scale. D. 373 on the Kelvin scale and -273 degrees on the Celsius scale. The second law of thermodynamics tells us that heat will not flow from A. hot to cold ever. B. cold to hot ever. C. hot to cold without external work. D. cold to hot without external work. The direction of natural processes is from states of A. higher order to lower order. B. lower order to higher order. C. disorganization to organization. D. disorder to equilibrium. As entropy in a system increases, energy in the system A. becomes more useful. B. becomes less useful. C. reaches equilibrium. D. is destroyed.