What experiments can demonstrate the reactivity series?

Experiments involving displacement reactions and reactions with water or acid can demonstrate the reactivity series.

The reactivity series is a list of metals, in order of reactivity from highest to lowest. It is used to determine the reactions that will occur in single displacement reactions. One way to demonstrate the reactivity series is through displacement reactions. In these experiments, a more reactive metal will displace a less reactive metal from its salt solution. For example, if you place a piece of zinc in a copper sulphate solution, the zinc will displace the copper because it is more reactive. The solution will turn from blue to colourless, indicating that the copper has been displaced.

Another way to demonstrate the reactivity series is by observing the reactions of metals with water or acid. More reactive metals will react more vigorously with these substances. For instance, potassium, a highly reactive metal, will react violently with water, producing hydrogen gas and heat that is sufficient to ignite the hydrogen. On the other hand, a less reactive metal like iron will only react slowly with steam, not with cold water, and a metal like copper does not react with water at all.

In addition, the reaction of metals with acid can also be used to demonstrate the reactivity series. Metals higher up in the series will react with acid to produce a salt and hydrogen gas. The speed and vigour of the reaction can give an indication of the metal's reactivity. For example, magnesium reacts with dilute hydrochloric acid to produce magnesium chloride and hydrogen gas, and the reaction is quite vigorous. However, copper, which is lower in the reactivity series, does not react with dilute hydrochloric acid.

These experiments can provide a visual and practical understanding of the reactivity series, reinforcing the theoretical knowledge.