H₂O — molecular geometry

The jump from a bond to a form. Oxygen brings six valence electrons: two go into O–H bonds, the other four sit as two lone pairs. Four electron domains, all repelling, arrange tetrahedrally — but lone pairs are fatter and push harder, so they squeeze the H–O–H angle down from the ideal 109.5° to 104.5°. The molecule is bent, and because it's bent the two bond dipoles don't cancel: water has a net dipole. That single fact — the bend — is why water dissolves, sticks, and floats as ice. Toggle CO₂ to see a molecule whose dipoles do cancel.

Bridge-Burners LLC · Fiddler · 2 bonds + 2 lone pairs → bent 104.5° → polar · anchor: AKASHA

State

electron domains4 (2 bond, 2 lone)
electron geometrytetrahedral
molecular shapebent
bond angle104.5°
net dipole1.85 D — polar

Bare numbers (H₂O)

O–H length95.8 pm (0.958 Å)
H–O–H angle104.5° (ideal tet. 109.5°)
dipole μ1.85 D
why bentlone-pair repulsion > bond-pair

Status discipline

LiteralO: 2 bonds + 2 lone pairs = 4 domains → tetrahedral; lone pairs push harder → 104.5° < 109.5°; bent + polar bonds → μ = 1.85 D → polar. CO₂: 2 domains, linear 180°, dipoles cancel, μ = 0.
BridgeVSEPR — pairs stay as far apart as possible; shape is the jump from 1-D bond to 3-D form; lone pairs are the invisible shapers.
SpeculativeVSEPR is a heuristic (great for main-group, not universal); localized lone pairs are a model — real H₂O has delocalized MOs. Clouds are schematic.