- #1
Brimley
- 77
- 0
Hello All,
I've been struggling to figure out how to solve for change of enthalpy and entropy. My reference text makes it look so easy but then gives an example where it provides totally different information. Here is the reference from the text:
"A Lead Acid Battery's measurments were taken at 27 deg C yielding the following data:
Open Circuit Voltage (OCV) = 2.05 V
n = 2
dE/dT = 0.2 mV/K
DeltaG, DeltaH, and DeltaS can be found using Gibbs Free Energy Equation and the formula DeltaG=DeltaH-T*DeltaS."
I have no idea how to find DeltaH or DeltaS given this data!
Here is how I solved for DeltaG:
DeltaG=-nFE=-2(98485)(2.05)=-403/788 J/mol (dived by 3600 s to convert to Wh/mol)
DeltaG = -112.163 Wh/mol
Where can I go from here?
Any and all help is greatly appreciated! --Brim
I've been struggling to figure out how to solve for change of enthalpy and entropy. My reference text makes it look so easy but then gives an example where it provides totally different information. Here is the reference from the text:
"A Lead Acid Battery's measurments were taken at 27 deg C yielding the following data:
Open Circuit Voltage (OCV) = 2.05 V
n = 2
dE/dT = 0.2 mV/K
DeltaG, DeltaH, and DeltaS can be found using Gibbs Free Energy Equation and the formula DeltaG=DeltaH-T*DeltaS."
I have no idea how to find DeltaH or DeltaS given this data!
Here is how I solved for DeltaG:
DeltaG=-nFE=-2(98485)(2.05)=-403/788 J/mol (dived by 3600 s to convert to Wh/mol)
DeltaG = -112.163 Wh/mol
Where can I go from here?
Any and all help is greatly appreciated! --Brim