### Gibbs Units

Posted:

**Mon Feb 25, 2019 7:53 pm**When calculating Gibbs free energy with the Delta G = -nFE equation and you are canceling units, is it necessary to change volts to J.C^-1 or can we keep the final answer in C.V?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=141&t=43024

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Posted: **Mon Feb 25, 2019 7:53 pm**

When calculating Gibbs free energy with the Delta G = -nFE equation and you are canceling units, is it necessary to change volts to J.C^-1 or can we keep the final answer in C.V?

Posted: **Mon Feb 25, 2019 8:15 pm**

Since Gibbs free energy is in terms of joules, it would be more accurate to change the units from V to J/C. You always want to make sure you cancel your units, not just out of necessity, but also because it's a very convenient way to check your work and make sure you're using the correct formula and correct units for your measured values. Hope this helps.

Posted: **Mon Feb 25, 2019 8:17 pm**

Hi! Faraday's constant has C/mol and E has V which is J/C so you are left with J/m which is how G is written. You don't need to convert because the units work out anyways. The reason why the mole remains even after the moles of electrons are multiplied in is because if represented the energy released/absorbed per mole of reaction.