In both water $(H_{2}O)$ and dimethyl ether $((CH_{3})_{2}O)$,the oxygen atom is the central atom and has the same hybridization,yet they have different bond angles. Which one has a greater bond angle? Give a reason.

(N/A) Dimethyl ether has a greater bond angle than water. In both molecules,the central oxygen atom is $sp^{3}$ hybridized with two lone pairs.
In dimethyl ether,the bond angle is greater $(111.7^{\circ})$ compared to water $(104.5^{\circ})$ due to the greater repulsive interaction between the two bulky methyl $(-CH_{3})$ groups than that between the two small $H$-atoms.
The $C$ atom of the $-CH_{3}$ group is attached to three $H$-atoms through $\sigma$-bonds,and the electron density of the $C-H$ bond pairs increases the steric repulsion,pushing the $C-O-C$ bond angle wider.