Why did Henri Moissan’s failed attempt to react fluorine with argon matter to chemistry?

In 1895, the French chemist Henri Moissan attempted to react fluorine—the most reactive element in the periodic table—with argon. His failure to produce a chemical compound was highly significant to the development of chemistry.1

This result, alongside other unsuccessful efforts to induce reactivity in argon, provided critical experimental evidence regarding the nature of atoms. It demonstrated the chemical inertness of the noble gases, which became a foundational concept in understanding atomic structure and chemical bonding.12

Specifically, these observations supported later theories, such as those proposed by Niels Bohr, Gilbert N. Lewis, and Walther Kossel, which established that the octet of electrons in the outermost shell is a highly stable arrangement. This realization explained why noble gases are relatively inactive and provided a framework for understanding how other elements gain, lose, or share electrons to achieve similar stability.1