Which one of the following ions has same number of unpaired electrons as those present in $\mathrm{V}^{3+}$ ion?

Question

Aicharya · Accepted Answer

$\begin{aligned}{ }_{23} \mathrm{~V} & =[\mathrm{Ar}] 3 d^3 4 s^2 \ \mathrm{~V}^{3+} & =[\mathrm{Ar}] 3 d^2 4 s^0 \Rightarrow 2 	ext { unpaired electrons } \ { }_{26} \mathrm{Fe} & =[\mathrm{Ar}] 3 d^6 4 s^2 \ \mathrm{Fe}^{3+} & =[\mathrm{Ar}] 3 d^5 4 s^0 \Rightarrow 5 	ext { unpaired electrons } \ { }_{28} \mathrm{Ni} & =[\mathrm{Ar}] 3 d^8 4 s^2 \ \mathrm{Ni}^{2+} & =[\mathrm{Ar}] 3 d^8 4 s^0 \Rightarrow 2 	ext { unpaired electrons } \ { }_{25} \mathrm{Mn} & =[\mathrm{Ar}] 3 d^5 4 s^2 \ \mathrm{Mn}{ }^{2+} & =[\mathrm{Ar}] 3 d^5 \Rightarrow 5 	ext { unpaired electrons } \ { }_{24} \mathrm{Cr} & =[\mathrm{Ar}] 3 d^5 4 s^1 \ \mathrm{Cr}^{3+} & =[\mathrm{Ar}] 3 d^3 4 s^1 \Rightarrow 3 	ext { unpaired electrons }\end{aligned}$ /

Which one of the following ions has same number of unpaired electrons as those present in $\mathrm{V}^{3+}$…

Solution