# What is the definition of entropy?

##### 2 Answers

Entropy by definition is the degree of randomness or disorder (chaos) in a system.

#### Explanation:

Entropy by definition is the degree of randomness or disorder (chaos) in a system.

Here is a complete lessons about entropy, I hope you find it helpful.

**Thermodynamics | Spontaneous Process & Entropy.**

**Entropy** (

*That is, it is a quantity that describes the number of microscopic arrangement possibilities for a given system.*

**STATISTICAL MECHANICS DEFINITION**

#\mathbf(S = k_BlnOmega)# where:

#Omega# is thenumber of microstatesthat collectively generate the same macrostate (observable).#k_B = 1.3806xx10^(-23) "J/K"# is theBoltzmann constant.

Take an **ensemble** (loosely-speaking, a group) **of molecules** that can be arranged in multiple ways.

The more ways you can arrange them, the more "disordered" they are. This corresponds with a greater

**THERMODYNAMICS DEFINITION**

A consistent *thermodynamic* definition of entropy is also:

#\mathbf(DeltaS >= (q)/T)#

(where

So another way you can think about it is that **for a given temperature**:

*The more the heat that you put into the system affects the microscopic arrangement of molecules, the more "disordered" the system is.*

**GENERAL CHEMISTRY DEFINITION**

This "disorder" is a definition of entropy you were introduced to in general chemistry, and is generalized to be *greater* for gases than for liquids, for instance.

Gases are **more freely-moving** than liquids, so gases can assume *more microstates* than the liquid phase of the same substance can. Thus, gases are more "disordered", and they have a **higher** entropy.