Master List of Important Lewis Structure Compounds for JEE/NEET

1. Octet Rule Molecules

H₂

N₂

O₂

F₂

Cl₂

Br₂

I₂

HF

HCl

HBr

HI

H₂O

H₂S

NH₃

PH₃

CH₄

SiH₄

CO₂

CS₂



—

2. Electron-Deficient Compounds

BeH₂

BeCl₂

BH₃

BF₃

BCl₃

AlCl₃



—

3. Odd-Electron Molecules

NO

NO₂

ClO₂

BrO₂

IO₂

O₂⁻

N₃ (azide radical, less common)



—

4. Resonance Species

O₃

CO₃²⁻

NO₂⁻

NO₃⁻

SO₂

SO₃

IO₃⁻

BrO₃⁻

ClO₃⁻

CN⁻

N₃⁻

HN₃



—

5. Polyatomic Ions

NH₄⁺

H₃O⁺

OH⁻

CN⁻

NO₂⁻

NO₃⁻

CO₃²⁻

HCO₃⁻

SO₃²⁻

SO₄²⁻

HSO₄⁻

PO₄³⁻

HPO₄²⁻

H₂PO₄⁻

ClO⁻

ClO₂⁻

ClO₃⁻

ClO₄⁻

BrO⁻

BrO₂⁻

BrO₃⁻

BrO₄⁻

IO⁻

IO₂⁻

IO₃⁻

IO₄⁻

I₃⁻

S₄O₆²⁻

S₂O₃²⁻



—

6. Hypervalent (Expanded Octet) Molecules

PCl₅

PF₅

SF₄

SF₆

ClF₃

BrF₃

IF₃

IF₅

IF₇

XeF₂

XeF₄

XeF₆

ICl₃



—

7. Xenon Compounds

XeF₂

XeF₄

XeF₆

XeO₃

XeO₄



—

8. Peroxides and Superoxides

H₂O₂

Li₂O₂

Na₂O₂

K₂O₂

MgO₂

CaO₂

SrO₂

BaO₂

KO₂

RbO₂

CsO₂



—

9. Peroxo Acids of N, P, S

HNO₄

ONOO⁻

H₃PO₅

H₄P₂O₈

H₂SO₅ (Caro’s acid)

H₂S₂O₈ (Marshall’s acid)



—

10. Sulfur Oxyanions

SO₃²⁻

SO₄²⁻

S₂O₃²⁻ (Thiosulfate)

S₄O₆²⁻ (Tetrathionate)

HSO₄⁻



—

11. Nitrogen Special Compounds

NO

NO₂

N₂O

N₂O₃

N₂O₄

N₂O₅

HN₃

N₃⁻



—

12. Carbon Special Compounds

CO

CO₂

C₃O₂ (Carbon suboxide)

CN⁻



—

13. Bromine–Oxygen Compounds

Br₂O

Br₂O₃

Br₂O₅

Br₂O₇

Br₃O₈

HBrO

HBrO₂

HBrO₃

HBrO₄

BrO⁻

BrO₂⁻

BrO₃⁻

BrO₄⁻



—

14. Iodine Compounds

IF₃

IF₅

IF₇

ICl₃

I₃⁻

HIO

HIO₂

HIO₃

HIO₄

H₅IO₆

IO⁻

IO₂⁻

IO₃⁻

IO₄⁻

I₂O

I₂O₃

I₂O₅

I₂O₇



—

Top 30 “Must-Do” Lewis Structures for JEE/NEET

NH₄⁺, H₃O⁺, BF₃, BeCl₂, CO, NO, NO₂, O₃, NO₂⁻, NO₃⁻, CO₃²⁻, SO₂, SO₃, SO₄²⁻, CN⁻, N₃⁻, HN₃, PCl₅, SF₄, SF₆, ClF₃, IF₃, IF₅, IF₇, XeF₂, XeF₄, XeF₆, I₃⁻, S₂O₃²⁻, S₄O₆²⁻.

If you can draw and analyze these 30 confidently (Lewis structure, formal charge, hybridisation, shape, bond angle, resonance), you’ll cover nearly all Lewis-structure-based questions in JEE and NEET.