Question

Rank these systems in order of decreasing entropy.

Rank from highest to lowest entropy. To rank items as equivalent, overlap them.

A) 1 mol carbon tetrafluoride gas at 273k 40L

B) 1 mol krypton gas at 273K 40L

C) 1/2 mol krypton gas at 100k 20L

D) 1 mol krypton gas at 273K 20L

E) 1/2 mol krypton liquid at 100K

F) 1 mol fluorine gas 273 K 40L

G) 1/2 mol krypton gas at 273K 20L

Thank you! Can you also provide an explanation how to figure it out?

Answer 1

Remember

1. The entropy is degree of disorderness, higher the disorderness higher the entropy.

2. If two gas have same number of moles, then the gas with more number of atoms in a molecule will have higher entropy ( due to more number of macrostates)

3. The smaller the volume the less the molecules can move around which also reduces the number of possible different states and hence less the entropy

4.In a colder gas the molecules or atoms are not so energetic and so do not occupy so many different energetic states and hence will have less entropy .

5. A liquid is more ordered than a gas, reducing its entropy.

So the order will be :

A > F > B> D > G > C > E