Equations 6.92 and 6.93 for the entropy and chemical potential involve the logarithm of the quantity VZintNvQ. Is this logarithm normally positive or negative? Plug in some numbers for an ordinary gas and discuss.

Short Answer

Expert verified

Yes, the logarithm is normally positive for ordinary gas as S=Nkln2is positive.

Step by step solution

01

Given information

We are given that,

Entropy and chemical potential involve the logarithm of the quantityVZintNvQ.

02

Explanation

We know that entropy is given as,

S=kNlnVN4πm3h2×UN32+52

Here, Uis the energy

and Vis volume

and Nis no. of molecules

Now, if energy and no. of molecules remain fixed,

S=NkVfVi

Here, Vfis the final volume

and Viis the initial volume

If Vf=2Vi

Then,

S=Nkln2

Similarly, the relationship between chemical potential can be determined to be positive.

From here, we can interpret that the logarithm of a given quantity is normally positive as both the entropy and chemical potential is positive.

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