Question

In the molecule $Xe{O}_2{F}_2$, there exists one $n$-fold axis of symmetry and in the molecule $Xe{O}_2{F}_4$, the number of $2$-fold axis of symmetry is $m$. The value of $m+n$ is :

• A. $6$
• B. $7$
• C. $8$
• D. $5$

Answer 1

The correct option is A $6$

In $Xe{O}_2{F}_2$, there exists one $2\left(n\right)$-fold axis of symmetry, while in $Xe{O}_2{F}_4$, there exists four $\left(m\right)$ $2$-fold axis of symmetry. The structures are given in the figure. Hence, $n=2$ and $m=4$.

Therefore, $n+m=2+4=6$