Number of valence electrons, molecular shape, hybridization, and bond angle of Cl2O7 and SF2
The correct answer and explanation is:
Sure! Let’s analyze Cl₂O₇ (dichlorine heptoxide) and SF₂ (sulfur difluoride) in terms of their valence electrons, molecular shape, hybridization, and bond angles.
1. Cl₂O₇ (Dichlorine Heptoxide)
Valence electrons:
- Cl has 7 valence electrons each → 7 × 2 = 14
- O has 6 valence electrons each → 6 × 7 = 42
Total valence electrons = 14 + 42 = 56 electrons
Molecular shape:
- Cl₂O₇ consists of two Cl atoms connected by an oxygen bridge (Cl–O–Cl) with other oxygens bonded to Cl atoms.
- Each Cl is surrounded by 4 oxygens: one bridging oxygen and three terminal oxygens.
- Central Cl atoms have tetrahedral electron geometry around them.
- The overall molecule is non-linear, and the shape around each Cl is tetrahedral but the molecule as a whole is bent or skewed due to bridging oxygen.
Hybridization:
- Around each Cl atom: sp³ (because of 4 electron groups: 4 bonds to O)
- Oxygen atoms have sp³ hybridization in most cases, especially the bridging oxygen with two bonds and two lone pairs.
Bond angles:
- Around Cl, the ideal tetrahedral angle is about 109.5°
- Due to lone pairs on oxygens and bridging structure, bond angles may slightly deviate, typically between 107° to 110°.
2. SF₂ (Sulfur Difluoride)
Valence electrons:
- S has 6 valence electrons
- Each F has 7 valence electrons → 7 × 2 = 14
Total valence electrons = 6 + 14 = 20 electrons
Molecular shape:
- Sulfur has 6 valence electrons, bonding with 2 fluorines and having 2 lone pairs.
- Electron geometry: tetrahedral (2 bonding pairs + 2 lone pairs)
- Molecular shape: bent (angular) due to lone pairs repelling bonding pairs.
Hybridization:
- Sulfur is sp³ hybridized (4 electron pairs: 2 bonding, 2 lone pairs).
Bond angle:
- Ideal tetrahedral angle: 109.5°
- Lone pair repulsion reduces bond angle to about 98° to 100° in SF₂.
Summary Table:
| Molecule | Valence Electrons | Molecular Shape | Hybridization | Bond Angle (approx.) |
|---|---|---|---|---|
| Cl₂O₇ | 56 | Bent/skewed tetrahedral | sp³ (Cl) | 107°–110° |
| SF₂ | 20 | Bent (angular) | sp³ (S) | ~98°–100° |
Explanation (300 words):
Dichlorine heptoxide (Cl₂O₇) is a chlorine oxide with two chlorine atoms connected via an oxygen bridge and multiple oxygen atoms bonded to each chlorine. To understand its bonding, count total valence electrons from chlorine (7 each) and oxygen (6 each), totaling 56 electrons. Each chlorine is bonded to four oxygens, forming a tetrahedral electron geometry with sp³ hybridization. The molecule’s shape around each Cl is approximately tetrahedral, but the presence of the bridging oxygen and lone pairs on oxygen atoms cause deviations from ideal angles, leading to bond angles around 107° to 110°.
Sulfur difluoride (SF₂) has 20 total valence electrons: sulfur contributes 6 and each fluorine 7. Sulfur forms two bonds with fluorines and retains two lone pairs, creating four electron domains around sulfur. This arrangement leads to a tetrahedral electron geometry and sp³ hybridization. However, because lone pairs repel bonding pairs more strongly, the molecular shape is bent, not linear, with bond angles compressed from the ideal 109.5° to approximately 98° to 100°. The difference in electronegativity between sulfur and fluorine also slightly influences the molecular geometry.
Both molecules demonstrate how lone pairs and multiple atoms affect molecular shape and bond angles. While both central atoms exhibit sp³ hybridization, the resulting shapes differ due to the number and arrangement of bonds and lone pairs. Cl₂O₇’s structure is more complex with bridging oxygens causing distortions, while SF₂’s shape is more straightforward with two lone pairs bending the molecule.