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The maximum work done by a voltaic cell is given by -nFE. Why the negative sign? From what I know, a battery does positive work on the load attached to it

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It is negative because it's the work done by the system on the surroundings. Here our system is taken as the cell.

Maximum work is also taken as the change in Gibbs free energy $(ΔG)$.

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  • $\begingroup$ But the system (the cell) is doing positive work on the surrounding (the load) $\endgroup$ – xasthor Sep 27 '17 at 12:52
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    $\begingroup$ Work done by the system should be positive, work done by the surroundings on the system should be negative. Does -nFE represent the work done on the battery? $\endgroup$ – xasthor Sep 27 '17 at 13:04
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    $\begingroup$ @xasthor Are you sure work done by system is taken positive ;) Are you aware of different conventions ? chemistry.stackexchange.com/questions/66088/… $\endgroup$ – Physicsapproval Sep 27 '17 at 14:17

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