would you expect an H2Se molecule to have a shape similar to that of water?
Give a reason for your answer?
Similar yes, there are two lone pairs. The is whether hybridization will take place (it doesn't). Actual H angles is about 91 degrees, compared to water of about 104 degrees. The point is that the molecule is not linear, but bent.
To determine whether an H2Se molecule would have a shape similar to that of water, we need to consider the molecular geometry and bonding characteristics of both molecules.
Water (H2O) has a bent or V-shaped molecular geometry. This is due to the presence of two lone pairs of electrons on the oxygen atom, which create repulsion and push the two hydrogen atoms closer together, resulting in a bent shape.
Hydrogen selenide (H2Se) consists of two hydrogen (H) atoms bonded to a selenium (Se) atom. Like water, H2Se does have two lone pairs of electrons on the central atom (Se). However, the difference lies in the electronegativity of the central atom.
Oxygen is more electronegative than selenium, meaning oxygen has a greater attraction for electrons. As a result, the oxygen atom in water tends to pull the bonding electrons closer to itself, creating a larger bond angle between the hydrogen atoms.
In the case of H2Se, the lesser electronegativity of selenium results in a smaller electron density around the central atom. This leads to weaker repulsion between the lone pairs of electrons, causing the hydrogen atoms to be slightly farther apart compared to water.
Therefore, while H2Se and water both have bent geometries, the bond angle in H2Se would be slightly larger than that in water. So, the shape of H2Se would be similar to that of water, but the bond angle would be slightly wider.