why doesn't copper displace iron?

i am looking at the reactioniron nitrate + copper--> no reactioncould someone explain why?

Iron is more reactive because it has a higher reduction potential than copper, meaning it will give away electrons more easily than copper, and so copper will not displace it in reaction because iron will want to give it's electrons to copper and copper will want to take it, which is already the case at the moment, therefore no reaction. You can explain it in terms of electronegativity - more electronegative atms attract electrons and the lesser ones give the electrons away to the more electronegative ones. The most electronegative atom is fluorine, and electronegativity, if you look at your periodic table, goes up as you go up and across a group. Iron is before copper on the periodic table, and so is less electronegative, which means it will give its electrons to copper. edited: the more electronegative atom will be the one that holds the electrons closer to the atom and doesn't want to give them away, i.e. being in its preferred state already. in solution there would be Fe ions and nitrate ions, correct? to displace the Fe ions, Cu would have to transfer electrons to the Fe ions so that Cu becomes the ion and Fe becomes the metal. this won't happen because of electronegativity, Cu does not want to give it's electrons to Fe and Fe does not want to receive them - they're both in their preferred state and nothing will change. and a transfer of electrons between the iron ions in solution and the copper metal (which doesn't happen) would be what displacing the metal is. this is why you don't get copper nitrate as a product.

Electronegativity Of Copper

This Site Might Help You. RE: why doesn't copper displace iron? i am looking at the reaction iron nitrate + copper--> no reaction could someone explain why?

The CN complexes the copper so strongly that it ionizes to only a very very limited extent. As a result, the amount of ionized copper in solution is so low that it's no longer noble to iron. The Nernst equation is what you want to look into. It relates that the nobility of one metal to another under conditions like this is not solely a function of their inherent deposition potentials, but their solution concentrations as well. No matter how much CuCN you have in solution, the complex is so tight that you have virtually zero copper in solution.