Question

Number of unpaired electrons in $O_2\left[As{F}_4\right]$ is :

Answer 1

Most stable oxidation state of As is +3.$O_2\left[As{F}_4\right]$ can be divided as $O_2^{+}$ and ${\left[As{F}_4\right]}^{-}$. Now we will find number of unpaired electrons in $O_2^{+}$ i.e., equal to 1 as we can see below with th help of its electronic configuration:

${\left({\sigma }_{1s}\right)}^2<{\left({\sigma }_{1s}^{\ast }\right)}^2<{\left({\sigma }_{2s}\right)}^2<{\left({\sigma }_{2s}^{\ast }\right)}^2<{\left({\sigma }_{2p_z}\right)}^2<{\left({\Pi }_{2p_x}\right)}^2={\left({\Pi }_{2p_y}\right)}^2<{\left({\Pi }_{2p_x}^{\ast }\right)}^1$