Which of the following are nucleophiles ?

Options

A. `PH_3`
B. `F^(Ө)`
C. `NH_3`
D. `H_2 O`

Explanation

To determine which of the given options are nucleophiles, we need to understand the definition and characteristics of nucleophiles.

### Step-by-Step Solution:

1. **Define Nucleophiles**:
- Nucleophiles are chemical species that are "nucleus-loving." They are characterized by having an abundance of electrons, which makes them electron-rich.
- They must contain at least one lone pair of electrons.
- Nucleophiles can be negatively charged or neutral.

2. **Analyze Each Option**:
- **Option 1: PH3 (Phosphine)**:
- Phosphorus (P) has five valence electrons. In PH3, phosphorus forms three bonds with hydrogen and retains one lone pair of electrons.
- Since PH3 has a lone pair, it qualifies as a nucleophile.

- **Option 2: F⁻ (Fluoride Ion)**:
- The fluoride ion has three lone pairs of electrons and carries a negative charge.
- Being negatively charged and having lone pairs, F⁻ is a strong nucleophile.

- **Option 3: NH3 (Ammonia)**:
- Nitrogen (N) has five valence electrons. In NH3, nitrogen forms three bonds with hydrogen and has one lone pair of electrons.
- The presence of a lone pair means NH3 is also a nucleophile.

- **Option 4: H2O (Water)**:
- Oxygen (O) has six valence electrons. In H2O, oxygen forms two bonds with hydrogen and retains two lone pairs of electrons.
- The two lone pairs indicate that H2O is also a nucleophile.

3. **Conclusion**:
- All the options provided (PH3, F⁻, NH3, and H2O) are nucleophiles because they all contain at least one lone pair of electrons and are electron-rich species.

### Final Answer:
All of the given options are nucleophiles: PH3, F⁻, NH3, and H2O.