How to Compare the Standard Molar Entropies of Related Compounds – Part 1

The standard molar entropy is referred to as the entropy content of one mole of a pure substance (typically) at the standard temperature and pressure.


Let’s recall that the second law of thermodynamics establishes the concept of entropy as a physical property of a thermodynamic system. For a molecule, entropy may be translational, rotational and vibrational.

Question:

Arrange the following in the increasing order of the standard molar entropies (SѲ):

HF, HCl, HBr & HI

Solution:


Click to enlarge the image

That looks not too difficult, or does it❓ Let Chemaficionado know at mychemistryhomework@gmail.com❗

References:

(1)    Wikipedia Contributors. Moment of inertia. Wikipedia. https://en.wikipedia.org/wiki/Moment_of_inertia.
(2)    Wikipedia Contributors. Second law of thermodynamics. Wikipedia. https://en.wikipedia.org/wiki/Second_law_of_thermodynamics.
(3)    Wikipedia Contributors. Entropy. Wikipedia. https://en.wikipedia.org/wiki/Entropy.(4)    Wikipedia Contributors. Standard molar entropy. Wikipedia.

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