## When a system can only be prepared in one way

Boltzmann Equation for Entropy: $S = k_{B} \ln W$

Katherine Grillo 1B
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### When a system can only be prepared in one way

What does it mean that a system can only be prepared in one way? And why does that mean S=0?

Chem_Mod
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### Re: When a system can only be prepared in one way

This is referring to when there is only one state/position available to the molecule(s). If there is only 1 position, then W (degeneracy)= 1number of molecules, and 1 raised to any power is still 1, then the ln(1)=0 so if S= kBln(W) then S=0. This tells us that the molecule or molecules do not possess any residual, or positional, entropy.

Christopher Anisi 2K
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### Re: When a system can only be prepared in one way

That means that the system can only be oriented in one way meaning that it only has one energy state or degeneracy value of 1. And when utilizing S=KBlnW assuming there is only residual energy involved that would give you an entropy value of 0.

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