Question

Why does xenon react with fluorine, whereas neon does not?

Short answer

Xenon reacts with fluorine due to its less tightly held valence electrons in the 5p subshell, which allows the highly reactive fluorine to form a bond. In contrast, neon's valence electrons in the 2p subshell are tightly held by its nucleus, making it difficult for fluorine to react with it.

Step-by-step solution

Understand the electronic configurations of xenon and neon

Both xenon and neon are noble gases and have complete electron shells. The electronic configurations for both elements are: - Neon (Ne): 1s² 2s² 2p⁶ - Xenon (Xe): 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ Step 2:

Compare the electronic configurations to determine reactivity

Neon has a completely filled 2p subshell, whereas xenon has a completely filled 5p subshell. The difference here is that xenon's valence electrons (5p electrons) are farther from the nucleus compared to neon's valence electrons (2p electrons). This means xenon's valence electrons are less tightly held by the nucleus and can more easily participate in chemical reactions. Step 3:

Understand the properties of fluorine

Fluorine (F) is a highly reactive element due to its high electronegativity (3.98 on the Pauling scale). It has a strong tendency to accept electrons, which makes it a powerful oxidizing agent. Fluorine can form a single bond to gain one more electron and complete its valence shell (2s² 2p⁵ to 2s² 2p⁶). Step 4:

Analyze the reactivity of xenon and neon with fluorine

Due to its high electronegativity, fluorine wants to gain an electron. Since xenon's valence electrons are farther from the nucleus and are less tightly held, the highly reactive fluorine can form a bond with xenon, resulting in compounds such as xenon hexafluoride (XeF₆). In contrast, neon's valence electrons (2p electrons) are held tightly by its nucleus, making it more difficult for fluorine to remove an electron and react with it. As a result, neon remains unreactive with fluorine. In conclusion, xenon reacts with fluorine due to its less tightly held valence electrons, which allows the highly reactive fluorine to form a bond. On the other hand, neon's valence electrons are tightly held by its nucleus, making it difficult for fluorine to react with it.