Which of the following species contains three bond pair and one lone pair around the central atom ?

Options

A. `H_(2)O`
B. `BF_(3)`
C. `NH_(2)^(-)`
D. `PCl_(3).`

Explanation

To determine which species contains three bond pairs and one lone pair around the central atom, we can follow these steps:

### Step 1: Understand the concept of bond pairs and lone pairs
- **Bond pairs** are pairs of electrons that are shared between two atoms to form a bond.
- **Lone pairs** are pairs of valence electrons that are not involved in bonding and belong to a single atom.

### Step 2: Identify the central atom in each species
We need to look at various species and identify their central atom. Common examples include:
- Ammonia (NH3)
- Phosphorus trifluoride (PF3)
- Bromine trichloride (BrCl3)

### Step 3: Determine the number of bond pairs and lone pairs
Now we will analyze some common species to see how many bond pairs and lone pairs they have:

1. **NH3 (Ammonia)**:
- Central atom: Nitrogen (N)
- Bond pairs: 3 (N-H bonds)
- Lone pairs: 1 (on nitrogen)
- Total: 3 bond pairs, 1 lone pair

2. **PF3 (Phosphorus trifluoride)**:
- Central atom: Phosphorus (P)
- Bond pairs: 3 (P-F bonds)
- Lone pairs: 1 (on phosphorus)
- Total: 3 bond pairs, 1 lone pair

3. **BrCl3 (Bromine trichloride)**:
- Central atom: Bromine (Br)
- Bond pairs: 3 (Br-Cl bonds)
- Lone pairs: 1 (on bromine)
- Total: 3 bond pairs, 1 lone pair

### Step 4: Conclusion
From the analysis, we can conclude that:
- **NH3**, **PF3**, and **BrCl3** all have three bond pairs and one lone pair around the central atom.

### Final Answer:
The species that contains three bond pairs and one lone pair around the central atom are **NH3**, **PF3**, and **BrCl3**.