In both water and dimethyl ether (CH3 —Ο — CH3 ), oxygen atom is central atom, and has the same hybridisation, yet they have different bond angles. Which one has greater bond angle? Give reason.
Dimethyl ether will have a greater bond angle. There will be more repulsion between bond pairs of CH3 groups attached in ether than between bond pairs of hydrogen atoms attached to oxygen in the water.
The carbon of CH3 in ether is attached to three hydrogen atoms through σ bonds and electron pairs of these bonds add to the electronic charge density on the carbon atom. Hence, the repulsion between two —CH3 groups will be more than that between two hydrogen atoms.