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Chemistry

Chemical Bonding and Molecular Structure

A Chemistry chapter of the NEET syllabus, and how to practise it for the computer-based exam.

Exam rules change between cycles. Confirm dates, syllabus and pattern against NTA's official site. We are not NTA.

Weightage: what the paper actually did

Chemical Bonding and Molecular Structure carried 4 questions in the NEET 2026 paper. One paper is a data point, not a destiny: NTA moves weight between chapters every cycle, which is why the weightage tables deserve care. The stable facts are the paper's shape: 180 questions, 720 marks, +4 right, −1 wrong.

Sample PYQs from this chapter

Real questions NTA asked from Chemical Bonding and Molecular Structure, with the answer and the working. Try before you peek.

Question 1 · NEET 2020

Identify a molecule which does not exist.
  1. A.Li2_{2}
  2. B.C2_{2}
  3. C.O2_{2}
  4. D.He2_{2}
Answer and explanation

Answer: D

He2\mathrm{He}_{2} does not exist because helium atoms have a complete outer shell and do not form stable bonds with each other. In contrast, Li2\mathrm{Li}_{2}, C2\mathrm{C}_{2}, and O2\mathrm{O}_{2} can form stable molecules. Chapter: Chemical Bonding and Molecular Structure.

Question 2 · NEET 2026

The highest occupied molecular orbital for Ne2\mathrm{Ne}_{2} is
  1. A.π2p\pi_{2p}
  2. B.σ2p\sigma_{2p}
  3. C.π2p∗\pi^{*}_{2p}
  4. D.σ2p∗\sigma^{*}_{2p}
Answer and explanation

Answer: D

Ne2\mathrm{Ne}_{2} has 20 electrons, enough to fill every molecular orbital derived from the 1s, 2s and 2p atomic orbitals. Filling in order, σ1s2σ1s∗2σ2s2σ2s∗2σ2p2π2p4π2p∗4σ2p∗2\sigma_{1s}^2\sigma^{*}_{1s}{}^2\sigma_{2s}^2\sigma^{*}_{2s}{}^2\sigma_{2p}^2\pi_{2p}^4\pi^{*}_{2p}{}^4\sigma^{*}_{2p}{}^2, the last two electrons enter σ2p∗\sigma^{*}_{2p}, which is therefore the HOMO. With every bonding orbital matched by its antibonding partner the bond order is zero, which is why Ne2\mathrm{Ne}_{2} does not exist as a stable molecule. NCERT Class 11, Chemical Bonding and Molecular Structure.

How to practise Chemical Bonding and Molecular Structure

Chapter by chapter, against real past-paper questions, on a screen: NEET is computer based from 2027. Read the chapter once, then attempt its PYQs until your accuracy stops climbing, and let the wrong answers tell you which lines to reread. If the chapter keeps refusing to stick, that has its own guide. There is also a free NEET mini mock with answers.

Nearby Chemistry chapters

Questions

How many questions did Chemical Bonding and Molecular Structure have in NEET 2026?

Chemical Bonding and Molecular Structure carried 4 questions in the NEET 2026 paper. Weightage shifts between cycles, so treat it as a probability, not a promise.

Where can I practise Chemical Bonding and Molecular Structure PYQs for NEET?

Explore available chapter-wise NEET practice in BrainIt, free until the 2027 exam. Review explanations and track chapter accuracy to guide your revision. Sample questions from this chapter are on this page.

Is Chemical Bonding and Molecular Structure important for NEET 2027?

It is part of the Chemistry syllabus the paper draws from, and NEET 2027 is computer based, so practise it on a screen. Your own accuracy in the chapter matters more than any weightage table: a heavy chapter you already score well on needs less time than a light one you keep missing.

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