WHY DOES NOT A STORM ARRANGE EVERYTHING IN THE STREET NEATLY?

We are going to look at the second law of thermodynamics at another angle.

Ice melts to water; coffee cools down to room temperature; when a balloon is pierced, air rushes out; glass cup falls down, broken into pieces; acid and base combines to form salt and water. The above actions and reactions takes place spontaneously. Our common sense and intuition vouch for it.

Why the reverse should not happen? Why not water turn into ice; why not air thrust itself into balloon; why not broken pieces join to form a cup; why particular direction for actions? The second law answers.
An action will take place only when disorder or entropy increases in the surroundings or universe. In short, change in entropy should be positive.

When the coffee looses heat, the room is slightly warmed up. The air from balloon rushes out and disturb the order in surroundings. The broken pieces have more disorder than a full cup. That is the reason for the direction of happenings.

Why disorder? Because of probability, when you shuffle a deck of cards, there is a strong probability that it will go into disorderly arrangement. It will never go into 1....10,j,q,k arrangement even though it is possible.

Instead of measuring the change in entropy in the universe, there is short cut called
Gibbs free energy = internal energy- temperature* entropy

If the entropy is positive, and if the Gibbs energy is negative, an action will happen spontaneously without any aids. If not, only forced (heating, pressuring etc,) actions will take place.
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THE EARTH, A SUPER ORGANISM

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DISORDER IS THE "ORDER OF THE DAY"

Imagine a balloon full of air. The air molecules are moving randomly inside the balloon. Let us pierce the balloon with a pin. The air rushes out. Why should not the air molecules stay inside the balloon safely and ignore the little hole? That is not the way the world works. The molecules always "want to occupy as many states as possible". Hence the air goes out in the open to occupy more volume. The things always goes into disorder (entropy) and the disorder increases with time. The above statement is what we call "second law of thermodynamics". Consider a cup of coffee on the table. Suppose the heat from entire room flows to your cup of coffee, the coffee will boil and the rest of the room will freeze. Freezing means bringing things to order and arrangement. It violates the second law. Hence it will never happen. Hence heat must flow from high ...

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