What is the shape and bond angle of a water molecule?

In a water molecule, the shape is classified as bent due to the two hydrogen atoms bonded to the central oxygen atom and the presence of two lone pairs of electrons on the oxygen. The molecular geometry is affected by the repulsion between the electron pairs; the lone pairs repel more strongly than the bonding pairs, which leads to a distortion from a tetrahedral arrangement into a V-shape or bent structure.

The bond angle in water is approximately 104.5 degrees. This deviation from the ideal tetrahedral angle of 109.5 degrees is observed because the lone pairs take up more space than the bonded hydrogen atoms, which alters the angle between the hydrogen-oxygen-hydrogen bonds. This results in the characteristic bent shape of the water molecule, essential for its unique properties, such as high surface tension and polarity.