Question

What does it mean when entropy is zero?

Answer 1

1. In any thermodynamics system entropy is defined as the degree of randomness in regard to any chemical reaction, any heat exchange, etc.
2. It is an extensive property and is denoted by “S”.
3. Change in entropy is calculated as the ratio of heat transfer at absolute temperature.
4. Mathematically it is represented as follows: $∆\mathrm{S}={\left(\frac{\mathrm{Q}}{\mathrm{T}}\right)}_{\mathrm{rev}}$where Q is heat transfer T is the absolute temperature and $∆\mathrm{S}$change in entropy.
5. If the entropy is zero then there is no change found in the system during any process.
6. Example: In the Adiabatic process no exchange of heat and mass transfer is possible and therefore, the entropy of the system is zero.