1 Answer
The TdS equation is a fundamental relation in thermodynamics that links changes in entropy (\(S\)) with changes in heat (\(Q\)) at a constant temperature. It is derived from the second law of thermodynamics and is commonly expressed as:
\[
dQ = T \, dS
\]
Here:
Key Points:
This equation is useful in understanding processes like heat transfer, phase changes, and in defining the direction of spontaneous processes in thermodynamics.
\[
dQ = T \, dS
\]
Here:
- \( dQ \) is the infinitesimal amount of heat added to the system.
- \( T \) is the absolute temperature (in Kelvin) at which the process occurs.
- \( dS \) is the infinitesimal change in entropy of the system.
Key Points:
- The equation represents a reversible process, meaning the system remains in thermodynamic equilibrium at all times.
- The TdS equation tells us how entropy changes when heat is transferred in a system.
- In a reversible process, the total heat added to the system is proportional to the change in entropy, with temperature acting as the proportionality constant.
This equation is useful in understanding processes like heat transfer, phase changes, and in defining the direction of spontaneous processes in thermodynamics.