Making use of an analogy between heat transfer in boiling and mass transfer in gas evolution at electrodes may be a helpful tool. Over decades, science in both fields has developed independently - except for a few tentative attempts. The problem is that one of the fields is mainly of interest in process engineering, whereas the other field is traditionally attributed to electrochemistry, although it is a purely physical domain. In fact, both fields exhibit many aspects in common. However, there are numerous particularities definitely limiting an analogy some of which have not been discerned so far. The important Nukiyama curve of boiling was set in analogy to a current-potential curve of gas-evolving electrodes. The formal resemblance of both curves obscures some essential distinctions. Congruities in analogy and their distinct limits are analyzed. (C) 2012 Elsevier Ltd. All rights reserved.