Due to this collision, they exert pressure on the walls. Now raise the temperature of the gas, we’ll notice that the molecules start to move faster, and they frequently collide with the walls of the box. Consider the molecules to be snooker balls that are continuously hitting the walls of the box and colliding amongst themselves. Imagine a system of gas molecules in a box.

And when two systems are somehow joined together, the entropy of the combined system is greater than the sum of entropies of the individual systems. The second law of thermodynamics states that the entropy of an isolated system always increases. He found that the entropy of a closed system will always increase. Rudolph Clasius was the person who coined the term.

The word entropy came from the study of heat and energy in the period 1850 to 1900. Our common experience says that disorder will tend to increase if things are left to themselves - That’s entropy in simple words! The second law of Thermodynamics forms the basis of this principle. Entropy is often called the arrow of time because matter in isolated systems tends to move from order to disorder. The arrow of time takes the concept even further ahead. In explaining our universe in terms of entropy, we’ve to consider how and why molecules and atoms are arranged in a definite way. Boltzmann took this concept further and related to the total number of microstates of a system. It was while taking into consideration this concept that entropy came into being. It all started with the second law of thermodynamics which states heat always flows from hot to cold. The concept of impermanence has evolved and taken the form of entropy in the language of science.

The law of entropy