Difference between revisions of "PChem312 f20 w13"

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====Example Problem 3====
 
====Example Problem 3====
 +
''(Please write out your complete solution and email to bes by next class period)''
 
[https://en.wikipedia.org/wiki/Polycyclic_aromatic_hydrocarbon Poly aromatic hydrocarbons] (<-- wiki link here) represent and interesting set of compounds.
 
[https://en.wikipedia.org/wiki/Polycyclic_aromatic_hydrocarbon Poly aromatic hydrocarbons] (<-- wiki link here) represent and interesting set of compounds.
  
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====Example Problem 4====
 
====Example Problem 4====
 +
''(Please write out your complete solution and email to bes by next class period)''
 
Calculate the entropy of vaporization for methanol, ethanol, and propanol under both constant pressure and constant volume conditions.
 
Calculate the entropy of vaporization for methanol, ethanol, and propanol under both constant pressure and constant volume conditions.
  

Revision as of 15:48, 11 November 2020

...return to Chem 312 - home

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Join ZOOM Lab Meeting

Monday, Nov 9, 2020

We will now highlight how to calculate entropy (ΔS) for four processes involving ideal gases:

Screen Shot 2020-11-09 at 8.42.24 AM.png
1) Reversible Isothermal Expansion or Compression
ViTi --> VfTi
Screen Shot 2020-11-11 at 7.31.58 AM.png
2) Constant P, V temperature change
ViTi --> ViTf
PiTi --> PiTf
Screen Shot 2020-11-11 at 7.37.17 AM.png
3) Changes in both V and T, constant P
ViTi -->V fTf
Screen Shot 2020-11-11 at 7.40.27 AM.png
4) Changes in both P and T, constant V
ViTi -->V fTf
Screen Shot 2020-11-11 at 7.47.04 AM.png

Example Problem 1

(Please write out your complete solution and email to bes by next class period)

Consider a gas undergoing the following change under constant pressure (1.00 bar) conditions; calculate the change in entropy (ΔS): Vi = 10.0 L; Ti = 298 K; Tf = 398 K

Example Problem 2

(Please write out your complete solution and email to bes by next class period)

Consider a gas undergoing the following change under constant volume (10.0 L) conditions; calculate the change in entropy (ΔS): Pi = 1.00 bar; Ti = 298 K; Tf = 398 K

Wednesday, Nov 11, 2020

Review contributions to ΔS due to ΔT, ΔV, ΔP for ideal gas/closed system.
Entropy of Phase Changes...

...continuing numbering from above...

5) Solid --> Liquid phase change (fusion/melting/freezing)
- under constant pressure
- under constant volume
6) Liquid --> gas phase change (vaporization/boiling/condensation)
- under constant pressure
- under constant volume

Example Problem 3

(Please write out your complete solution and email to bes by next class period) Poly aromatic hydrocarbons (<-- wiki link here) represent and interesting set of compounds.

PAH.PNG

Calculate the entropy of fusion for 5 PAHs.

Example Problem 4

(Please write out your complete solution and email to bes by next class period) Calculate the entropy of vaporization for methanol, ethanol, and propanol under both constant pressure and constant volume conditions.

Thursday, Nov 12, 2020

Friday, Nov 13, 2020