E° cell equation

[tbearOD]

i was wondering when figuring out the value of E° cell which equation do i use?

1. cathode - anode

or

2. cathode + anode

my OAT kaplan book is giving my the second equation but the kaplan MCAT book is giving me the first equation

---

Members don't see this ad.

 

[Glaucisxtra]

Well they can both be correct. It depends on the value of the anode. It’s cathode - anode, but if anode is negative, it becomes cathode + anode.