Which one of the following has pyramid shape ?

Options

A. `NH_(3)`
B. `SiF_(4)`
C. `H_(2)O`
D. `BF_(3)`

Answer

To determine which of the given molecules has a pyramidal shape, we will analyze each option based on their molecular geometry and hybridization.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- A) NH3 (Ammonia)
- B) SiF4 (Silicon Tetrafluoride)
- C) H2O (Water)
- D) BF3 (Boron Trifluoride)

2. **Analyze NH3 (Ammonia)**:
- Ammonia (NH3) has a nitrogen atom bonded to three hydrogen atoms and has one lone pair of electrons.
- The hybridization of nitrogen in NH3 is **sp³**.
- The presence of the lone pair pushes the hydrogen atoms down, resulting in a **trigonal pyramidal shape**.
- **Conclusion**: NH3 has a pyramidal shape.

3. **Analyze SiF4 (Silicon Tetrafluoride)**:
- Silicon Tetrafluoride (SiF4) has a silicon atom bonded to four fluorine atoms.
- The hybridization of silicon in SiF4 is also **sp³**.
- There are no lone pairs on the silicon atom, resulting in a **tetrahedral shape**.
- **Conclusion**: SiF4 does not have a pyramidal shape.

4. **Analyze H2O (Water)**:
- Water (H2O) has an oxygen atom bonded to two hydrogen atoms and has two lone pairs of electrons.
- The hybridization of oxygen in H2O is **sp³**.
- The two lone pairs push the hydrogen atoms closer together, resulting in a **bent or V-shaped structure**.
- **Conclusion**: H2O does not have a pyramidal shape.

5. **Analyze BF3 (Boron Trifluoride)**:
- Boron Trifluoride (BF3) has a boron atom bonded to three fluorine atoms.
- The hybridization of boron in BF3 is **sp²**.
- There are no lone pairs on the boron atom, resulting in a **trigonal planar shape**.
- **Conclusion**: BF3 does not have a pyramidal shape.

### Final Conclusion:
The only molecule among the options that has a pyramidal shape is **NH3 (Ammonia)**.

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