Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
Which one of the following ions has same number of unpaired electrons as those present in $\mathrm{V}^{3+}$ ion?
Chemistryd and f Block ElementsTS EAMCETTS EAMCET 2014
Options:
  • A $\mathrm{Fe}^{3+}$
  • B $\mathrm{Ni}^{2+}$
  • C $\mathrm{Mn}^{2+}$
  • D $\mathrm{Cr}^{3+}$
Solution:
1331 Upvotes Verified Answer
The correct answer is: $\mathrm{Ni}^{2+}$
$\begin{aligned}{ }_{23} \mathrm{~V} & =[\mathrm{Ar}] 3 d^3 4 s^2 \\ \mathrm{~V}^{3+} & =[\mathrm{Ar}] 3 d^2 4 s^0 \Rightarrow 2 \text { unpaired electrons } \\ { }_{26} \mathrm{Fe} & =[\mathrm{Ar}] 3 d^6 4 s^2 \\ \mathrm{Fe}^{3+} & =[\mathrm{Ar}] 3 d^5 4 s^0 \Rightarrow 5 \text { unpaired electrons } \\ { }_{28} \mathrm{Ni} & =[\mathrm{Ar}] 3 d^8 4 s^2 \\ \mathrm{Ni}^{2+} & =[\mathrm{Ar}] 3 d^8 4 s^0 \Rightarrow 2 \text { unpaired electrons } \\ { }_{25} \mathrm{Mn} & =[\mathrm{Ar}] 3 d^5 4 s^2 \\ \mathrm{Mn}{ }^{2+} & =[\mathrm{Ar}] 3 d^5 \Rightarrow 5 \text { unpaired electrons } \\ { }_{24} \mathrm{Cr} & =[\mathrm{Ar}] 3 d^5 4 s^1 \\ \mathrm{Cr}^{3+} & =[\mathrm{Ar}] 3 d^3 4 s^1 \Rightarrow 3 \text { unpaired electrons }\end{aligned}$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.