Question

The molecule that has ONLY one lone pair of electrons on xenon is _ _ _.

• A. XeF$_2$
• B. XeF$_4$
• C. XeO$_2$F$_2$
• D. XeO$_3$F$_2$

Hint:

Use steric number = bond pairs + lone pairs to quickly determine number of lone pairs in noble gas compounds

Answer 1

The Correct Option is C

Step 1: Use the steric number.
Lone pairs on xenon equal the steric number minus the number of bonded atoms.

Step 2: Check each molecule.
XeF$_2$ has three lone pairs, XeF$_4$ has two, XeO$_3$F$_2$ has none. XeO$_2$F$_2$ has two Xe to O and two Xe to F bonds with one lone pair.

Step 3: Pick the one with a single lone pair.
Only XeO$_2$F$_2$ has exactly one lone pair, giving a see-saw shape.

Step 4: Answer.
\[ \boxed{\text{XeO}_2\text{F}_2} \]