Hi, I'm trying to write an equation to show what happens when mercury liquid (Hg) is placed on a block of aluminium (Al). But I'm having some problems. Here's my current line of thinking (I haven't yet worked out any subscripts so I will just use the atomic symbols): Al has an aluminium oxide layer, which is denoted by AlO. Do I include this aluminium oxide in the left hand side of the equation? The way I see it is the mercury is being added to both the aluminium and the aluminium oxide. And do I add the oxygen in the air to the left hand side. The oxygen in the air will react with the aluminium. Hg + O + Al + AlO -> Some result As for the result I'm not sure what it should be. The mercury never bonds with the aluminium does it? I think that the mercury reacts with the aluminium oxide (is AlO a gas or a solid): Hg(s) + AlO(?) -> Hg(s) + Al(s) + O(g) And then the oxygen reacts with the aluminium to form aluminium oxide again: Al(s) + O(g) -> AlO(?) From my working out it the reaction never ends. So I've either made a great discovery or I've made a mistake . Can someone give me some pointers as to the final result? Thanks.