Lewis Structure Generator
Reviewed ion guide

OH⁻ Lewis Structure: Hydroxide Ion

Hydroxide has one O–H single bond, three lone pairs on oxygen and an overall −1 charge. The extra electron belongs in the total before the structure is drawn.

Reviewed July 16, 2026 · Educational Lewis model

Generate OH⁻Ion drawing rules

Quick answer

Valence electrons

O contributes 6, H contributes 1 and the negative charge adds 1: 8 total.

Lewis structure

[H–O]⁻ with three lone pairs on oxygen.

Formal charge

Oxygen is −1; hydrogen is 0. The sum is −1.

How to draw OH⁻

  1. Count 6 + 1 + 1 charge electron = 8 electrons.
  2. Connect H and O with one single bond, using 2 electrons.
  3. Place the remaining 6 electrons as three lone pairs on oxygen.
  4. Put the complete structure in brackets and write the − charge outside.
  5. Check hydrogen has a duet and oxygen has an octet.

Why the charge is on oxygen

The formal-charge equation is valence − nonbonding − half the bonding electrons. Oxygen has 6 − 6 − 1 = −1. Hydrogen has 1 − 0 − 1 = 0.

Common mistake: drawing neutral OH with the same electron count. Neutral OH is a radical with 7 valence electrons; OH⁻ has 8.