The reactivity of elements, including noble gases, is primarily determined by the electron configuration and the availability of valence electrons. Noble gases are characterized by having a full valence electron shell, making them chemically inert and less reactive compared to other elements. However, with heavier noble gases, such as xenon (Xe), there are some circumstances where they can exhibit reactivity.
Heavier noble gases have larger atomic sizes and more electrons compared to their lighter counterparts. In the case of xenon, it has a total of 54 electrons, with the electron configuration being 2-8-18-18-8. The valence shell of xenon is the fifth energy level (n=5) and contains eight valence electrons.
Although noble gases generally have a stable electron configuration, heavier noble gases can potentially undergo reactions under specific conditions. The reactivity of xenon and other heavier noble gases arises from their ability to accommodate additional electrons in their valence shell, despite it being relatively full.
By providing energy, such as through the use of powerful oxidizing agents or by exposure to extreme conditions, it is possible to excite or ionize xenon atoms. This can lead to the formation of xenon compounds, where xenon shares electrons with other elements to complete its valence shell.
For example, xenon can form compounds such as xenon hexafluoride (XeF6) or xenon tetrafluoride (XeF4) by bonding with fluorine. These compounds demonstrate the reactivity of xenon's valence electrons, which can participate in chemical reactions despite being part of an otherwise inert noble gas.
In summary, while noble gases are typically inert, heavier noble gases like xenon can exhibit reactivity under certain conditions. The larger atomic size and increased number of valence electrons in heavier noble gases allow for the accommodation of additional electrons, enabling the formation of compounds and increased reactivity.