Question

Question: How many unpaired electrons are present in each of the following in the ground state:$\mathbf{O}\mathbf{,}{\mathbf{O}}^{\mathbf{+}}\mathbf{,}{\mathbf{O}}^{\mathbf{-}}\mathbf{,}\mathbf{Os}\mathbf{,}\mathbf{Zr}\mathbf{,}\mathbf{S}\mathbf{,}\mathbf{F}\mathbf{,}\mathbf{Ar}$?

Short answer

The total number of valence electrons present in$\mathrm{O},{\mathrm{O}}^{+},{\mathrm{O}}^{-},\mathrm{Os},\mathrm{Zr},\mathrm{S},\mathrm{F},\mathrm{Ar}$ are $2,3,1,4,2,2,1$and$0$ .

Step-by-step solution

Step 1:

ATOM ELECTRONIC CONFIGURATION

1. $\mathrm{O}$ $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^4$
2. ${\mathrm{O}}^{+}$ $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^3$
3. ${\mathrm{O}}^{-}$ $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^5$
4. $\mathrm{Os}$ $\left[\mathrm{Xe}\right]4f^{14}5d^{6}6s^2$
5. $\mathrm{Zr}$ $\left[\mathrm{Kr}\right]4d^{2}5s^2$
6. $\mathrm{S}$ $\left[\mathrm{Ne}\right]3s^{2}3p^4$
7. $\mathrm{F}$ $\left[\mathrm{He}\right]2s^{2}2p^5$
8. $\mathrm{Ar}$ $\left[\mathrm{Ne}\right]3s^{2}3p^6$

Step 2:

$\mathrm{O},{\mathrm{O}}^{+}$and ${\mathrm{O}}^{-}$have and unpaired electron in their$2\mathrm{p}$ orbital.

$\mathrm{Os}$has unpaired electrons in its$5\mathrm{d}$ orbital.

$\mathrm{Zr}$has unpaired electrons in its $4\mathrm{d}$orbital.

$\mathrm{S}$has unpaired electrons in its $3\mathrm{p}$orbital.

$\mathrm{F}$has unpaired electrons in its $2\mathrm{p}$orbital.

$\mathrm{Ar}$has no unpaired electron and its octet is complete.