Question

Which of the following fluorides of Xenon does not exist?

• A. \( \text{XeF}_3 \)
• B. \( \text{XeF}_2 \)
• C. \( \text{XeF}_6 \)
• D. \( \text{XeF}_4 \)

Hint:

Remember the common fluorides of Xenon: \( \text{XeF}_2 \), \( \text{XeF}_4 \), and \( \text{XeF}_6 \). The oxidation state of Xenon in its stable fluorides is typically even (+2, +4, +6) due to its even number of valence electrons. Fluorides with odd oxidation states of Xenon are generally not stable.

Answer 1

The Correct Option is A

Xenon is a noble gas, and for many years it was considered to be chemically inert.
However, Neil Bartlett's work in 1962 showed that Xenon can react with highly electronegative elements like fluorine.
Several fluorides of Xenon have been synthesized and characterized.
These include \( \text{XeF}_2 \), \( \text{XeF}_4 \), and \( \text{XeF}_6 \).
Let's consider the oxidation states of Xenon in these fluorides: - In \( \text{XeF}_2 \), the oxidation state of Xe is +2.
- In \( \text{XeF}_4 \), the oxidation state of Xe is +4.
- In \( \text{XeF}_6 \), the oxidation state of Xe is +6.
The formation of these fluorides can be explained by the excitation of electrons from the filled \( 5p \) orbitals of Xenon to the empty \( 5d \) orbitals, resulting in unpaired electrons that can form bonds with fluorine atoms.
The number of unpaired electrons available determines the number of fluorine atoms that can bond with Xenon.
Xenon has an even number of valence electrons (8), so it tends to form compounds where its oxidation state is even (+2, +4, +6).
\( \text{XeF}_3 \) would require Xenon to have an oxidation state of +3, which involves having an odd number of unpaired electrons.
Due to the electronic configuration of Xenon and the energy required for excitation, the formation of stable Xenon compounds with odd oxidation states is not generally observed under normal conditions.
While some unstable or transient species with odd oxidation states might exist, \( \text{XeF}_3 \) is not a well-characterized, stable fluoride of Xenon.
Therefore, \( \text{XeF}_3 \) does not exist as a stable compound.