S and delta S

[Amanda Mac 1C]

Can someone tell me the difference between S (like in the Boltzmann equation) and delta S besides the fact that delta S is the change in entropy? How would we find S?

[Michaela Capps 1l]

S is the residual entropy while delta S is the change in entropy.

[Julia Cheng 2J]

You would usually use delta S to find the change in entropy of a reaction (so some change to the system has to happen in order for there to be a delta S). We've only been using S to find the entropy of a molecule as a result of its structure (so there doesn't have to be any change in its state).

[Lisa Tang 1C]

You can find the absolute entropy by using the Boltzmann equation S=k_B*lnW. k_B is Boltzmann's constant (1.38x10^-23J/K).

[YashDeshmukh1D]

S as described by the Boltzmann equation describes positional entropy. That is, the total entropy or disorder as a result of the orientations of the molecules, rather than their thermal entropy, which is determined by their motion. Delta S usually combines both these quantities to describe how entropy changes over the course of a reaction.