Ask a chemistry question about the strength of metal reactivity

It is recommended that you find a university textbook on inorganic chemistry and review it* again, preferably while also studying the basic concepts of physical chemistry*. There is more than one criterion for determining metal reactivity.

The reactivity of metals depends not only on the number of valence electrons but also on factors such as the electron affinity of metal atoms, atomic radius, electron configuration, and their position in the periodic table. Metallic activity refers to a metal’s ability to release electrons when it reacts with other substances. Generally, metals located in the left and upper parts of the periodic table have relatively higher reactivity, as they tend to lose electrons more easily to form positive ions. Although aluminum (Al) is located further to the right in the periodic table than iron (Fe) (in group 3A), it is more reactive than iron mainly because: 1. Atomic structure: Aluminum’s atomic radius is smaller than that of iron, and the electrons are closer to the nucleus; this results in a stronger shielding effect from the inner electrons on the outermost electrons, making the outermost electrons less stable. As a result, aluminum loses electrons more easily than iron. 2. Electron configuration: Although aluminum has 3 electrons in its outermost shell, while iron has 2 electrons in its outermost shell, all of aluminum’s outer electrons are in the same energy level; the repulsive forces between them make it easier for them to break away from the atom. 3. Standard electrode potential: The standard electrode potential of aluminum is much more negative than that of iron; in other words, aluminum loses electrons more easily to form \( Al^{3+} \), while it is relatively easier for iron to form \( Fe^{2+} \) or \( Fe^{3+} \). 4. Thermodynamic stability: The \( Al^{3+} \) ions formed by aluminum in reactions are thermodynamically more stable than the \( Fe^{2+} \) or \( Fe^{3+} \) ions formed by iron. In summary, although iron has fewer outer electrons than aluminum, aluminum as a whole loses its electrons more easily and participates in chemical reactions more readily; therefore, in the series of metal reactivity, aluminum is more reactive than iron. .