Learn

Friday, 9 October

NEET UG 2023 · Chemistry · Question 70

NEET 2023 Chemistry, question 70

Question 70 of the NEET 2023 paper (code G6) is a Chemistry question from Chemical Bonding and Molecular Structure. Its idea, MO Energy Order and s-p Mixing, was asked only this once in NEET 2017–2026. The NTA final answer key gives option 2.

Updated 2026-10-08

Q70 · Chemistry

The correct order of energies of molecular orbitals of N2_2 molecule, is :

  1. 1σ1s<σ∗1s<σ2s<σ∗2s<(π2px=π2py)<(π∗2px=π∗2py)<σ2pz<σ∗2pz\sigma1s<\sigma^*1s<\sigma2s<\sigma^*2s<(\pi2p_x=\pi2p_y)<(\pi^*2p_x=\pi^*2p_y)<\sigma2p_z<\sigma^*2p_z
  2. 2σ1s<σ∗1s<σ2s<σ∗2s<(π2px=π2py)<σ2pz<(π∗2px=π∗2py)<σ∗2pz\sigma1s<\sigma^*1s<\sigma2s<\sigma^*2s<(\pi2p_x=\pi2p_y)<\sigma2p_z<(\pi^*2p_x=\pi^*2p_y)<\sigma^*2p_zOfficial answer
  3. 3σ1s<σ∗1s<σ2s<σ∗2s<σ2pz<(π2px=π2py)<(π∗2px=π∗2py)<σ∗2pz\sigma1s<\sigma^*1s<\sigma2s<\sigma^*2s<\sigma2p_z<(\pi2p_x=\pi2p_y)<(\pi^*2p_x=\pi^*2p_y)<\sigma^*2p_z
  4. 4σ1s<σ∗1s<σ2s<σ∗2s<σ2pz<σ∗2pz<(π2px=π2py)<(π∗2px=π∗2py)\sigma1s<\sigma^*1s<\sigma2s<\sigma^*2s<\sigma2p_z<\sigma^*2p_z<(\pi2p_x=\pi2p_y)<(\pi^*2p_x=\pi^*2p_y)

Official answer: option 2 · NTA final answer key

Same idea

The only question on MO Energy Order and s-p Mixing

No other NEET paper from 2017–2026 tested this exact idea.

MO Energy Order and s-p Mixing: every question and how it was framed

The chapter

Chemical Bonding and Molecular Structure in ten years of NEET

24 questions from 2017–2026, asked in 10 of 10 papers, about 2.3 a paper. Molecular Orbital Theory alone had 8.

Chapter analysisStudy this chapterPractise this chapter

Chemical Bonding and Molecular Structure: questions per paper

0243’172’181’192’203’212’222’234’242’253’26