back to directory
NEET CHEMISTRYOrganic Chemistry – Some Basic Principles and Techniques Easy

Question

Considering the state of hybridisation of carbon atoms, find out the molecule among the following which is linear.

A

HC≡CH\text{HC}\equiv\text{CH}

B

CH2=CH−CH2−C≡CH\text{CH}_2=\text{CH}-\text{CH}_2-\text{C}\equiv\text{CH}

C

CH3−CH2−CH2−CH3\text{CH}_3-\text{CH}_2-\text{CH}_2-\text{CH}_3

D

CH3−CH=CH−CH3\text{CH}_3-\text{CH}=\text{CH}-\text{CH}_3

Step-by-Step Solution

For an organic molecule to be completely linear, all the carbon atoms making up the chain must possess a linear geometry. According to VSEPR theory and hybridisation concepts, spsp hybridised carbon atoms have a linear geometry with a bond angle of 180∘180^\circ.

  • HC≡CH\text{HC}\equiv\text{CH} (Ethyne): Both carbon atoms are spsp hybridised, resulting in a strictly linear molecule.
  • CH3−CH2−CH2−CH3\text{CH}_3-\text{CH}_2-\text{CH}_2-\text{CH}_3: All carbon atoms are sp3sp^3 hybridised, giving them a tetrahedral geometry (109.5∘109.5^\circ bond angle) and making the carbon chain zig-zag.
  • CH3−CH=CH−CH3\text{CH}_3-\text{CH}=\text{CH}-\text{CH}_3: Contains sp3sp^3 (tetrahedral) and sp2sp^2 (trigonal planar) hybridised carbon atoms, making the molecule non-linear.
  • CH2=CH−CH2−C≡CH\text{CH}_2=\text{CH}-\text{CH}_2-\text{C}\equiv\text{CH}: Contains sp2sp^2, sp3sp^3, and spsp hybridised carbon atoms, making the overall structure non-linear. Therefore, ethyne is the only linear molecule among the choices.

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 consideringhybridisationcarbonmoleculefollowing

More Organic Chemistry – Some Basic Principles and Techniques Questions

View all

Which one of the following pairs is isostructural (i.e., having the same shape and hybridization)?

A.$\text{BCl}_3$ and $\text{BrCl}_3$
B.$\text{NH}_3$ and $\text{NO}_3^-$
C.$\text{NF}_3$ and $\text{BF}_3$
D.$\text{BF}_4^-$ and $\text{NH}_4^+$
MediumSolve

Among the following, isoelectronic species are:

A.$CO_{2}, NO_{2}$
B.$NO_{2}^{-}, CO_{2}$
C.$CN^{-}, CO$
D.$SO_{2}, CO_{2}$
EasySolve

Which one of the following pairs of species have the same bond order?

A.$\text{CO}$, $\text{NO}$
B.$\text{O}_2^-$, $\text{CN}^-$
C.$\text{CN}^-$, $\text{NO}^+$
D.$\text{N}^+$, $\text{CN}^+$
MediumSolve

In a regular octahedral molecule, $MX_{6}$, the number of $X–M–X$ bonds at 180º is:

A.Two
B.Six
C.Four
D.Three
EasySolve

Which of the following pairs of ions are isoelectronic and isostructural?

A.CO₃²⁻, SO₃²⁻
B.ClO₃⁻, CO₃²⁻
C.SO₃²⁻, NO₃⁻
D.ClO₃⁻, SO₃²⁻
MediumSolve

Which orbital does the additional electron occupy when $O_{2}$ is converted to the $O_{2}^{-}$ ion?

A.$\pi$ orbital
B.$\sigma^{*}$ orbital
C.$\sigma$ orbital
D.$\pi^{*}$ orbital
MediumSolve

A species that does not exhibit paramagnetism is:

A.$N_{2}^{+}$
B.$O_{2}^{-}$
C.$CO$
D.$NO$
MediumSolve

The total number of $\pi$-bond electrons in the following structure is:

A.4
B.8
C.12
D.16
EasySolve

Why 32,000+ students choose TopperSquare

Everything you need to crack NEET

15,000+ Chapter MCQs

Physics, Chemistry, Biology — chapter-wise, topic-wise practice

AI Performance Analytics

Know your weak topics. Get a personalised study plan.

Full NEET Mock Tests

180 questions, timed, with detailed score analysis

PYQ Sets 2010–2024

15 years of past papers with solved explanations

Start Practising Free

No credit card · 30-second signup · Free forever plan included

This neet chemistry practice question is part of the TopperSquare free question bank. TopperSquare offers 15,000+ chapter-wise NEET MCQs across Physics, Chemistry, and Biology with detailed step-by-step explanations, full mock tests, NEET PYQs (2010–2024), and an AI-powered performance analytics dashboard. browse all neet practice questions → · practice chemistry sets →

Explore more subjects:Physics MCQs•Chemistry MCQs•Biology MCQs•Botany MCQs•Zoology MCQs•NEET Mock Tests•NEET PYQs