Question

$H-O-H$ bond angle in $H_{2}O$ is $104.5^{\circ }$ and not $109^{\circ }28$ because of:

• A. lone pair-lone pair repulsion
• B. lone pair-bond pair repulsion
• C. bond pair-bond pair repulsion
• D. high electronegativity of oxygen

Answer 1

Answer: (A)

The hybridisation of oxygen in water molecule is $s{p}^3$ so water must be tetrahedral and have bond angle $109^{\circ }28$. But due to the presence of two lone pair of electrons on oxygen atom (repulsion between lone pair-lone pair) the bond angle decreases about $104.5^{\circ }$ and the geometry becomes distorted tetrahedral or $V$-shape