In this book, the objective has been to set down a number of questions, largely numerical problems, to help the student of electrochemical science. No collection of problems in electrochemistry has previously been published. The challenge which faces the authors of such a book is the breadth of the material in modern electrochemistry, and the diversity of backgrounds and needs of people who may find a "problems book" in electrochemistry to be of use. The general intention for Chapters 2-11 has been to give the first ten questions at a level which can be dealt with by students who are undergoing instruction in the science of electrochemistry, but have not yet reached graduate standard in it. The last two questions in Chapters 2-11 have been chosen at a more advanced standard, corre­ sponding to that expected of someone with knowledge at the level of a Ph.D. degree in electrochemistry.