 In the single displacement reaction of a metal replacing a metal ion from its compound, a more reactive metal will displace a less reactive metal from its compound. We have a solution of silver nitrate, and we're going to add some copper wire to the solution. The copper is a more reactive metal than the silver, and the copper metal will replace the silver ion from its solution. As the reaction occurs, silver metal will form on the copper wire. After about 30 minutes, we see that we formed a very large amount of solid, silver crystals. The solution has turned blue due to the formation of the copper plus 2 ions.