Chemical Thermodynamics Chapter 4 Chemistry Class 12 Textbook Solution

3. Answer in brief.

ii. What is entropy? Give its units.

Answer:-

Entropy is a measure of the degree of molecular disorder or randomness within a system.

The change in entropy of a system (ΔS) is determined by the amount of heat transferred (Q_{rev}) in a reversible manner, divided by the absolute temperature (T) in Kelvin at which this transfer occurs. Mathematically, it can be expressed as:

ΔS = Q_{rev} / T

The units of entropy are joules per Kelvin (J K^{-1}).

Note: Entropy, or its change (ΔS), is a state function. It solely depends on the initial and final states of the system and is independent of the specific path taken to connect these two states.