Which of the following has largest bond angle ?

Options

A. `H_(2)O`
B. `F_(2)O`
C. `Cl_(2)O`
D. `H_(2)S`

Answer

To determine which of the given molecules has the largest bond angle, we will analyze each option step by step.

### Step 1: Analyze H2S
- **Structure**: H2S (Hydrogen sulfide) has a bent molecular geometry due to the presence of two hydrogen atoms bonded to a sulfur atom.
- **Bond Angle**: The bond angle in H2S is approximately 90 degrees. This is because sulfur does not undergo hybridization, and the bonding involves p-orbitals, leading to a smaller bond angle.

### Step 2: Analyze H2O
- **Structure**: H2O (Water) has a bent shape with oxygen at the center and two hydrogen atoms.
- **Bond Angle**: The ideal bond angle for a tetrahedral arrangement is 109.5 degrees, but due to the presence of two lone pairs on oxygen, the bond angle is reduced to approximately 104 degrees.

### Step 3: Analyze F2O
- **Structure**: F2O (Difluorooxide) also has a bent shape with oxygen at the center and two fluorine atoms.
- **Bond Angle**: The bond angle in F2O is around 102 degrees, which is smaller than that of H2O due to the presence of the electronegative fluorine atoms that increase lone pair-bond pair repulsion.

### Step 4: Analyze Cl2O
- **Structure**: Cl2O (Dichlorine monoxide) has a bent structure with oxygen at the center and two chlorine atoms.
- **Bond Angle**: The bond angle in Cl2O is approximately 110.9 degrees. This larger bond angle is due to the delocalization of the lone pair of electrons on oxygen into the empty d-orbitals of chlorine, which reduces lone pair-bond pair repulsion and increases bond pair-bond pair repulsion.

### Conclusion
Comparing the bond angles:
- H2S: ~90 degrees
- H2O: ~104 degrees
- F2O: ~102 degrees
- Cl2O: ~110.9 degrees

The molecule with the largest bond angle is **Cl2O** with a bond angle of **110.9 degrees**.

### Final Answer
**Cl2O has the largest bond angle.**

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