Pair of transition metal ions having the same number of unpaired electrons is
Solution
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<th class="tg-baqh">Configuration</th>
<th class="tg-baqh">No. of unpaired e$^-$</th>
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<td class="tg-baqh">(1)</td>
<td class="tg-0lax">$\mathrm{V}^{3+}$</td>
<td class="tg-baqh">$\Rightarrow$</td>
<td class="tg-0lax">$[\mathrm{Ar}] 3 \mathrm{~d}^3 4 \mathrm{~s}^0$<br></td>
<td class="tg-baqh">3</td>
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<td class="tg-0lax">$\mathrm{Co}^{2+}$</td>
<td class="tg-baqh">$\Rightarrow$</td>
<td class="tg-0lax">$[\mathrm{Ar}] 3 \mathrm{~d}^7 4 \mathrm{~s}^0$<br></td>
<td class="tg-baqh">3</td>
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<td class="tg-baqh">(2)</td>
<td class="tg-0lax">$\mathrm{Ti}^{2+}$</td>
<td class="tg-baqh">$\Rightarrow$</td>
<td class="tg-0lax">$[\mathrm{Ar}] 3 \mathrm{~d}^2 4 \mathrm{~s}^0$<br></td>
<td class="tg-baqh">2</td>
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<td class="tg-0lax">$\mathrm{Co}^{2+}$</td>
<td class="tg-baqh">$\Rightarrow$</td>
<td class="tg-0lax">$[\mathrm{Ar}] 3 \mathrm{~d}^7 4 \mathrm{~s}^0$<br></td>
<td class="tg-baqh">3</td>
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<td class="tg-baqh">(3)</td>
<td class="tg-0lax">$\mathrm{Fe}^{3+}$</td>
<td class="tg-baqh">$\Rightarrow$</td>
<td class="tg-0lax">$[\mathrm{Ar}] 3 \mathrm{~d}^5 4 \mathrm{~s}^0$<br></td>
<td class="tg-baqh">5</td>
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<td class="tg-0lax">$\mathrm{Cr}^{2+}$</td>
<td class="tg-baqh">$\Rightarrow$</td>
<td class="tg-0lax">$[\mathrm{Ar}] 3 \mathrm{~d}^4 4 \mathrm{~s}^0$<br></td>
<td class="tg-baqh">4</td>
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<td class="tg-baqh">(4)</td>
<td class="tg-0lax">$\mathrm{Ti}^{3+}$</td>
<td class="tg-baqh">$\Rightarrow$</td>
<td class="tg-0lax">$[\mathrm{Ar}] 3 \mathrm{~d}^1 4 \mathrm{~s}^0$<br></td>
<td class="tg-baqh">1</td>
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<td class="tg-0lax">$\mathrm{Mn}^{2+}$</td>
<td class="tg-baqh">$\Rightarrow$</td>
<td class="tg-0lax">$[\mathrm{Ar}] 3 \mathrm{~d}^5 4 \mathrm{~s}^0$<br></td>
<td class="tg-baqh">5</td>
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<p>So $\mathrm{V}^{2+} \& \mathrm{Co}^{2+}$ same number of unpaired electron.</p>
About this question
Subject: Chemistry · Chapter: d and f Block Elements · Topic: Properties of Transition Metals
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