In which of the following bond angle is maximum

Options

A. (a) `NH_3`
B. (b) `NH_4^+`
C. (c) `PCl_3`
D. (d) `SCl_2`

Answer

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

### Step 1: Analyze NH4⁺ (Ammonium Ion)
- **Structure**: In NH4⁺, nitrogen is the central atom bonded to four hydrogen atoms.
- **Geometry**: The molecular geometry is tetrahedral.
- **Bond Angle**: In a perfect tetrahedral structure, the bond angle is 109.5 degrees.

### Step 2: Analyze NH3 (Ammonia)
- **Structure**: In NH3, nitrogen is bonded to three hydrogen atoms and has one lone pair.
- **Geometry**: The molecular geometry is trigonal pyramidal due to the presence of the lone pair.
- **Bond Angle**: The bond angle in NH3 is slightly less than 109.5 degrees due to lone pair-bond pair repulsion, approximately 107 degrees.

### Step 3: Analyze PCl3 (Phosphorus Trichloride)
- **Structure**: In PCl3, phosphorus is the central atom bonded to three chlorine atoms and has one lone pair.
- **Geometry**: The molecular geometry is also trigonal pyramidal.
- **Bond Angle**: Similar to NH3, the bond angle in PCl3 is less than 109.5 degrees due to lone pair-bond pair repulsion, but it is typically around 100-107 degrees.

### Step 4: Analyze SCl2 (Sulfur Dichloride)
- **Structure**: In SCl2, sulfur is the central atom bonded to two chlorine atoms and has two lone pairs.
- **Geometry**: The molecular geometry is bent.
- **Bond Angle**: The bond angle in SCl2 is significantly reduced due to the presence of two lone pairs, typically around 104 degrees or less.

### Conclusion
After analyzing all the options, we find:
- NH4⁺ has a bond angle of 109.5 degrees.
- NH3 has a bond angle of approximately 107 degrees.
- PCl3 has a bond angle of around 100-107 degrees.
- SCl2 has a bond angle of approximately 104 degrees.

Thus, the molecule with the maximum bond angle is **NH4⁺ (Ammonium Ion)**, with a bond angle of 109.5 degrees.

### Answer:
**Option B: NH4⁺**

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