What will happen if a piece of Zn metal is placed in a solution of \(\mathrm{Al}^{3+}\) ions?

To understand what happens when zinc metal is placed into a solution of aluminum ions, we need to understand displacement reactions. These reactions involve a more reactive metal displacing a less reactive metal from its compound.

The core idea is that certain metals have the ability to “kick out” other metals from their ionic compounds, due to their higher reactivity. This process is like a competitive match where the stronger player (the more reactive metal) wins the spot from the weaker player (the less reactive ion in solution).

Chemical reactivity is a measure of how easily an element will react with other substances. It's a critical concept when predicting the outcome of chemical reactions, including displacement reactions. Reactivity is influenced by various factors including electron configuration and the element's position in the periodic table.

In our step-by-step exercise, we compared the reactivity of zinc and aluminum by referring to the reactivity series—a chart that ranks elements by their reactivity. This chart is incredibly useful for predicting which reactions will occur and which will not. The position of an element in this series is a direct indication of its willingness to participate in chemical reactions by losing electrons.

The reactivity series is particularly useful when discussing metals, as it can be used to predict outcomes in reactions. Metals higher in the series are more likely to lose electrons and react compared to those lower in the series. Metal reactivity affects various applications, from the extraction of metals to their corrosion resistance.

For instance, in the exercise provided, zinc is less reactive than aluminum. Thus, according to the reactivity series, it cannot replace aluminum in a displacement reaction. Understanding the metal reactivity concept allows us not just to predict the possibility of a reaction, but also to foresee the stability of certain metals in different environments, which is pivotal in material science and engineering.