Final answer:
In CH₃CH₂OH, the carbon atoms demonstrate tetrahedral geometry with bond angles close to 109.5° due to sp³ hybridization, while the bond angle around the oxygen in the OH group is approximately 104.5° because of the two lone pairs of electrons.
Step-by-step explanation:
To predict the bond angles for all bonds in CH₃CH₂OH, we must consider the electronic geometry around each carbon atom and also the oxygen atom. The carbon atoms in CH₃CH₂OH are surrounded by four groups of electrons, which implies an sp³ hybridization. Due to the tetrahedral electronic geometry, the H-C-H bond angles and H-C-C bond angles in a CH₃ group and in the CH₂ group are close to 109.5°. This is consistent with the Valence Shell Electron Pair Repulsion (VSEPR) theory, which predicts such bond angles for a tetrahedral geometry.
However, when it comes to the bond angle around the oxygen atom in the hydroxyl (OH) group, due to the presence of two lone pairs of electrons, we expect a bent shape with the bond angle slightly less than the tetrahedral angle. This typically results in an O-H bond angle that is approximately 104.5°.
In summary, in CH₃CH₂OH, we can expect to see H-C-H and C-C-H bond angles around 109.5° for the carbon atoms, while the H-O-H bond angle will be around 104.5°, modified slightly due to the presence of the lone pairs on oxygen.