( ( ( ( overpotential ( The difference ) ) ( in ( ( ( ( the ( electrode potential ) ) ( of ( ( an electrode ) ( between ( its ( equilibrium potential ) ) ) ) ) ) and ) ( its ( operating potential ) ) ) ) ) ( when ( ( a current ) ( is flowing ) ) ) ) . )
(ROOT (S (VP (VB overpotential) (NP (DT The) (NN difference)) (PP (IN in) (NP (NP (NP (DT the) (JJ electrode) (NN potential)) (PP (IN of) (NP (NP (DT an) (NN electrode)) (PP (IN between) (NP (PRP$ its) (NN equilibrium) (NN potential)))))) (CC and) (NP (PRP$ its) (VBG operating) (NN potential)))) (SBAR (WHADVP (WRB when)) (S (NP (DT a) (NN current)) (VP (VBZ is) (VP (VBG flowing)))))) (. .)))
overpotential The difference in the electrode potential of an electrode between its equilibrium potential and its operating potential when a current is flowing.
(ROOT (S (NP (NP (DT The) (NN difference)) (PP (IN between) (NP (NP (DT the) (JJ theoretical) (JJ half-reaction) (NN reduction) (NN potential)) (CC and) (NP (NP (DT the) (JJ actual) (NN voltage)) (VP (VBN required)))))) (VP (VBZ is) (VP (VBN called) (S (ADJP (JJ overpotential))))) (. .)))