    Question

# What is the electronic configuration of Chromium in $\left[\mathrm{Cr}\left({\mathrm{NH}}_{3}{\right)}_{6}{\right]}^{3+}$?

Open in App
Solution

## Electronic configuration:It is defined as the distribution of electrons of an atom in an atomic orbital.The general notation of electronic configuration is ${s}^{a}{p}^{b}{d}^{c}$ where $s,p,$ and $d$ represents the subshell and $a,b$ and $c$ represents the number of electrons present in the subshell as superscript. Atomic number:The symbol of Chromium is $Cr$.Atomic number of Chromium is $24$ which is a transition element and it belongs to ${4}^{th}$ period and ${6}^{th}$ group of periodic table.As the atomic number is equal to the number of electrons present in a neutral element. So, the number of electrons are $24$.The electronic configuration of Chromium should be $1{s}^{2}2{s}^{2}2{p}^{6}3{s}^{2}3{p}^{6}4{s}^{2}3{d}^{4}$.But as we know that the half-filled and fully filled electronic configuration are more stable. So, one electron is transferred from $4s$ orbital to $3d$ orbital.Thus, the electronic configuration of Chromium is $1{s}^{2}2{s}^{2}2{p}^{6}3{s}^{2}3{p}^{6}4{s}^{1}3{d}^{5}$.The electronic configuration of Chromium in noble gas notation is represented as $\left[Ar\right]3{d}^{5}4{s}^{1}$ where $\left[Ar\right]$ represents the inert core of Argon which is a noble gas and $3{d}^{5}4{s}^{1}$ represents the valence shell electronic configuration of Chromium.Hence, the electronic configuration of Chromium is $1{s}^{2}2{s}^{2}2{p}^{6}3{s}^{2}3{p}^{6}4{s}^{1}3{d}^{5}$ or $\left[Ar\right]3{d}^{5}4{s}^{1}$.  Suggest Corrections  0      Similar questions  Explore more