http://img225.imageshack.us/img225/5959/111fc6.jpg
唔明點解會有pink colour
唔好答我因為alkaline
2007-07-13 13:09:32 · 1 個解答 · 發問者 2003 2 in 科學 ➔ 化學
Fe is more reactive (at a higher position in electrochemical series) than Cu. Thus, Fe is oxidized to Fe2+ and releases electrons.
Fe(s) → Fe2+(aq) + 2e-(aq)
Electrons flows from Fe to Cu. In the presence of water, oxygen in water accepts electrons and is reduced to give OH-(aq) ions.
2H2O(l) + O2(g/aq) + 4e- → 4OH-(aq)
The OH-(aq) formed will change the phenolphthalein indicator to pink.
2007-07-14 04:36:03 · answer #1 · answered by Uncle Michael 7 · 0⤊ 0⤋