Difference between revisions of "PChem312 f20 w13"

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====Example Problem 4====
 
====Example Problem 4====
 +
Calculate the entropy of vaporization for methanol, ethanol, and propanol under both constant pressure and constant volume conditions.
  
 
===Thursday, Nov 12, 2020===
 
===Thursday, Nov 12, 2020===
  
 
===Friday, Nov 13, 2020===
 
===Friday, Nov 13, 2020===

Revision as of 15:48, 11 November 2020

...return to Chem 312 - home

Join Zoom Lecture Meeting
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

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

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