Since antiquity, humanity has sought to understand the fundamental nature of matter. The concept of chemical elements has gradually refined, evolving from Aristotle's four elements to the modern classification inaugurated by Mendeleev in the 19th century.
Each element is now defined by the number of protons in its nucleus, which determines its unique chemical properties. The study of the electronic and nuclear structure of elements has allowed us to understand their behavior in terms of bonding, reactivity, and stability.
The applications are vast: light elements like hydrogen and oxygen are crucial in biochemistry and energy, while transition metals are involved in catalysis, electronics, or industry. Radioactive elements, on the other hand, are used in nuclear energy production and medicine, illustrating the central role of chemical elements in technological and scientific advancements.
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