Final answer:
Metallic elements change their electronic structure by losing electrons to form ions during reactions. The ease of electron loss and the resulting changes in electronic structure relate to metallic character, which is influenced by atomic size and ionization energy trends on the periodic table.
Step-by-step explanation:
When metallic elements react, their electronic structure changes, typically by losing electrons to form positively charged ions known as cations. As metals react, they tend to achieve a more stable electronic configuration, often reaching the electron configuration of the nearest noble gas. For example, thinking about a typical transition metal like iron, we can observe its electronic structure changing when it forms 2+ or 3+ ions, losing two or three outer electrons, respectively.
The metallic character of an element is related to how easily it can lose electrons, which increases as you go down a group on the periodic table because the atomic radius increases and the ionization energy decreases. This results in outer electrons being farther from the nucleus and less tightly bound, facilitating their removal. The electronic structure changes during reactions are significant because they govern the properties of the element, such as conductivity and malleability, which are characteristics of metals.
It's important to remember that in ordinary chemical reactions, while the electronic structure of atoms is altered, the nuclear structure remains unchanged. The protons and neutrons within the nucleus do not change, ensuring that the identity of the element is maintained even as its electronic structure varies during reactions that form ions or compounds.