Lewis Structure Generator
Propionic Acid · C₂H₅COOH

C₂H₅COOH Lewis Structure

The molecule combines an ethyl group with a carboxylic-acid carbonyl and O–H bond.

Open C₂H₅COOH in the generatorSee drawing steps
C₂H₅COOH
CH₃CH₂—C(=O)—O—H
Reviewed stored connectivity; detailed electron placement is explained below
Total valence electrons30
Reviewed connectivityCH₃CH₂—C(=O)—O—H
GeometryMixed: tetrahedral alkyl carbons and planar carboxyl carbon
Support levelReviewed guide

Propionic Acid overview

The stored Lewis connectivity is CH₃CH₂—C(=O)—O—H. The molecule combines an ethyl group with a carboxylic-acid carbonyl and O–H bond.

How to draw C₂H₅COOH

  1. Count 30 valence electrons. Include charge adjustments before drawing.
  2. Use the reviewed connectivity CH₃CH₂—C(=O)—O—H. Do not infer a different isomer from the formula alone.
  3. Place the required single, double or multiple bonds. Keep a running electron total.
  4. Complete terminal valence shells and add lone pairs or formal charges. The molecule combines an ethyl group with a carboxylic-acid carbonyl and O–H bond.
  5. Verify the total electron count and geometry. The reviewed geometry is Mixed: tetrahedral alkyl carbons and planar carboxyl carbon.

Why this example matters

The molecule combines an ethyl group with a carboxylic-acid carbonyl and O–H bond.

Scope and model limits

The neutral acid is shown. Its conjugate base has two resonance-equivalent C–O bonds after deprotonation.

Common mistakes

  • Using 28 instead of 30 valence electrons
  • Attaching the acid hydrogen to carbon
  • Making the neutral C–O bonds equivalent

Last reviewed: 2026-07-16. Educational reference only; verify graded work with course materials.