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# Entropy watch

1. 1. How could the molar entropy of H2O(g) be estimated experimentally?
2. Explain why the molar entropy of O2 is larger than that of O.

1. Is this sth to do with measuring heat capacities at various temperatures down to very low temperatures? Then plotting a graph of heat capacity versus temperature? The area under the graph is the standard entropy?

If it's for H2O gasous I guess the measurements of heat capacities should be done only for this state?

2. I've got no idea

Please, I need some help with these...
Am I right with the 1st question to some extent?

Thanks

1. You use the second law of thermodynamics dS = q/T, so if you measure the heat changes at low temperatures (not the heat capacities).

2. The molecule will have greater internal entropy than the atom thanks to having more internal components, a bond that can vibrate etc
3. Thanks a lot.
Indeed the title doesn't match the content. I realised that when I typed in entropy to see if someone has answered my questions.

(Original post by EierVonSatan)

1. You use the second law of thermodynamics dS = q/T, so if you measure the heat changes at low temperatures (not the heat capacities).

2. The molecule will have greater internal entropy than the atom thanks to having more internal components, a bond that can vibrate etc
4. (Original post by EierVonSatan)
2. The molecule will have greater internal entropy than the atom thanks to having more internal components, a bond that can vibrate etc
Other than bonds vibrating what other components could you list?

In an O2 molecule there are more electrons so the number of rearrangements of these electrons is greater than for a single atom and its own electrons. Hence the higher entropy of O2.
Is it correct?

Anything else?
5. (Original post by a fresh student)
Thanks a lot.
Indeed the title doesn't match the content. I realised that when I typed in entropy to see if someone has answered my questions.
You can edit the title of your post. One the first post select "Edit" > "Go advanced"
6. I suppose I could have altered the title myself

(Original post by a fresh student)
Other than bonds vibrating what other components could you list?

In an O2 molecule there are more electrons so the number of rearrangements of these electrons is greater than for a single atom and its own electrons. Hence the higher entropy of O2.
Is it correct?

Anything else?
That's what I was refering to about more internal components, the sub atomic structure and the various arragements in which they can exist

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