Which statement concerning overvoltage is false? A)Overvoltage is the additional voltage above the calculated voltage required to bring about electrolysis. B)Overvoltage is often due to a high activation energy for the reaction at one electrode. C)Overvoltage is small for half-reactions involving the formation of O₂(g)or H₂(g). D)Overvoltage must be experimentally determined.

Question

Quizplus · Accepted Answer

Overvoltage is the additional voltage required to initiate a redox reaction at an electrode, and it is often due to a high activation energy. However, some half-reactions involving the formation of gases such as O2 or H2 have a very high overvoltage, while others involving the formation of gases such as Cl2 or Br2 have a much lower overvoltage. Therefore, statement C is false because overvoltage can be significant for some half-reactions even if they involve the formation of gases. Statements A, B, and D are all true.

Which Statement Concerning Overvoltage Is False