The amount of heat that any chemical process releases or absorbs can be measured using an insulated container called a calorimeter. There are several versions, the most basic statement being that the entropy of all perfect crystalline solids is zero at absolute zero temperature. The third law of thermodynamics emerged in the early 20th century.The second law of thermodynamics is the one that disallows decrease of entropy with respect to time.This makes possible the seeming paradox of refrigeration. The pressure of a gas, for example, can decrease, but simultaneously its temperature will decrease while its caloric energy content remains constant. Energy can change from one form to another, but it can be neither created nor destroyed. The first law of thermodynamics asserts a universal conservation of energy, stated in the context of thermodynamic systems.The phenomenon known as entropy has been formalized as the second of these three laws of thermodynamics: It is conceivable that the process would reverse so that the ink molecules would reconstitute and form once again into a black blob, but probability working in conjunction with the arrow of time predicts otherwise. You can look at this as the ink dispersing because it has experienced an increase in volume. The ink mixes with the water, at first due to the collision between the two substances, and finally due to random molecular motion. The ink will mix with the water, quickly dissipating and becoming invisible as its concentration decreases. Into a vessel of clear water, introduce a small amount of black ink. The principle can be easily demonstrated in the lab or even as a simple table-top demonstration at home. The usual ways energy spreads out is when the system increases in volume or when the system is heated. So increasingly the “disorder” explanation is giving way to the idea that entropy describes energy spreading out or dispersing. Educators increasingly feel that the concept of entropy as the disorder can be confusing. It was once widely taught that entropy is a measure of disorder.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |