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NEET CHEMISTRYOrganic Chemistry – Some Basic Principles and Techniques Easy

Question

Among the following, isoelectronic species are:

A

CO2,NO2CO_{2}, NO_{2}

B

NO2−,CO2NO_{2}^{-}, CO_{2}

C

CN−,COCN^{-}, CO

D

SO2,CO2SO_{2}, CO_{2}

Step-by-Step Solution

Isoelectronic species are defined as atoms, ions, or molecules that possess the same total number of electrons . To identify the isoelectronic pair, we calculate the total electron count for the species in the correct option using their atomic numbers (ZZ) and charges:

  1. CN−CN^{-} (Cyanide ion): Carbon (Z=6Z=6) + Nitrogen (Z=7Z=7) + 1 (for the negative charge) = 14 electrons .
  2. COCO (Carbon monoxide): Carbon (Z=6Z=6) + Oxygen (Z=8Z=8) = 14 electrons .

Since both CN−CN^{-} and COCO have exactly 14 electrons, they are isoelectronic . Other pairs, such as CO2CO_{2} (22 electrons) and NO2NO_{2} (23 electrons), do not have the same number of electrons and are therefore not isoelectronic .

Exam Context & Concepts Covered

This question aligns with the NEET CHEMISTRY syllabus, specifically targeting concepts from Organic Chemistry – Some Basic Principles and Techniques . Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

CHEMISTRYOrganic Chemistry – Some Basic Principles and Techniques followingisoelectronicspecies

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A.$\text{BCl}_3$ and $\text{BrCl}_3$
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C.$\text{NF}_3$ and $\text{BF}_3$
D.$\text{BF}_4^-$ and $\text{NH}_4^+$
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A.$\text{CO}$, $\text{NO}$
B.$\text{O}_2^-$, $\text{CN}^-$
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A.Two
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A.CO₃²⁻, SO₃²⁻
B.ClO₃⁻, CO₃²⁻
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A.4
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