Displacement Reactions of Metals in Aqueous Solutions Decreasing order of reactivity Magnesium, zinc, iron, copper, silver
Consider two metals magnesium and zinc. Magnesium is higher than zinc in the metal reactivity series. This means that magnesium loses electrons more readily than zinc. Thus magnesium atoms loses electrons to become magnesium ions, while zinc ions are forced to gain electrons to become zinc atoms. Thus magnesium displaces zinc metal from zinc sulphate solution. On the other hand, there is no reaction between zinc metal and magnesium sulphate solution. Other displacement reactions can be explained similarly.
Cu (s) + 2Ag + (aq) Cu 2+ (aq) + 2Ag (s) Cu (s) + 2Ag + (aq) Cu 2+ (aq) + 2Ag (s) Higher Higher Lower Lower Salt Salt More More Less Less More More Less Less