Can anyone explain entrophy?

Question

Entropy is the
measure of the disorder
in a system. When energy
transforms from one form to
another, it goes toward greater
disorder, therefore greater entropy!

What does all of that mean? Does it mean that things have a natural drive to get messy? Or that entropy increases as enegy transforms such as the enegy of the sun is absorbed by trees and the trees produce oxygen and that is absorebed by humans and humans produce CO^2 and so on? Would that cycle constitute as increasing entropy?

CAn someone explain?

Answer 1

It's a tough concept to grasp. Here are some good explainations:


http://www.madsci.org/posts/archives/oct98/909712896.Ph.r.html
http://www.madsci.org/posts/archives/mar97/859247407.Ev.r.html
http://www.madsci.org/posts/archives/nov99/942797163.Gb.r.html

Answer 2

The suggestion that entropy is a "measure of disorder" can be misleading, because some physical systems, when "stirred", can actually result in something like having more order. For example, if one has a jar of sand and gravel and larger rocks that is thoroughly mixed, and if one should put it on a vibrating table, the larger rocks will float to the top, while the sand will drift to the bottom, with the gravel more or less inbetween. The idea that entropy is a "measure of disorder" is a 19th century idea that has now been superseded by a more sophisicated understanding, that allows the possibility of emergence of complexity even with increasing overall entropy.
The idea that things start in perfection, only to steadily degrade into imperfection and finally chaos, is an ancient Greek idea, and badly suited for today's concepts of entropy, disorder and emergent complexity. Some recent experiments in physics have even succeeded in violating the 2nd law of thermodynamics, a "law" which in fact was only assumed axiomatically, but never actually proven.

Answer 3

This is how i think of it
On a chemical scale. Thing of phase change.
1 mole of liquid water occupies a certain volume, the molecules are more tightly packed together than in gas.
When heat is added, the particles are given more energy to move, the flow apart from eachother. You see that by 1 mole of steam taking up more volume. Thats an increase in entropy.

You can think of it on a men's urinal scale too. If there are 7 urinals and the bathroom is empty. Which urinal do you use, it makes sense to use the one closes to the door because its quicker, but you most likely chose the one farthest away. You want to space out.

How about if there is a guy already using the urinal the farthest away. Now it makes more sense to use the one closest to the door, but you probably use the urinal right next to the one closest to the door. WHy go right next to the guy or take the one closest the door, when you are given space.

Answer 4

Entropy is the universe's natural tendency toward disorder. Basically, you are right that things have a natural tendency to get messy. You must use energy inorder to create order (e.g. pick up your room). Biological systems must use energy to create and utilize these cycle of which you speak, so the cycles constitute a decrease in randomness and a decrease in entropy, but they have to use energy to make it happen. Let me know if you need more help.

Answer 5

Things like to get less ordered; you could say messy but then people with messy rooms know where everything is so there is really an order to the mess!

Rather than messy, think "more random". A solid is organized with a regular repeating pattern; not random at all. It has less entropy than a liquid which is is less ordered and a liquid is even less ordered than a gas. So, the gas has the most entropy or the most "randomness:.

Answer 6

The fact of the matter (you got it right about the messy business) that entropy is usually describing problems encountered when trying to control nature.

In nature things appear to be messy when they are not fully understood. Many scientists and engineers are looking to create order out of what they perceive as chaos..., but their efforts are construed as entropy when natural laws try to right themselves in a man made controlled environment.

Answer 7

Something that represents an increase in entropy would be combustion: the decomposition of ordered molecules into more simple CO2 and water.

Answer 8

It's what happens in a battery sittin' on a shelf. SHELF LIFE. The loss of energy in a closed system.