The number of lone pairs of electrons on central atom of `H_(2)O,SnCl_(2),PCl_(3)and XeF_(2)` respectively are:

Options

A. `2,1,1,3`
B. `2,2,1,3`
C. `3,1,1,2`
D. `2,1,2,3`

Explanation

To determine the number of lone pairs of electrons on the central atom for the given molecules \( H_2O \), \( SnCl_2 \), \( PCl_3 \), and \( XeF_2 \), we will analyze each molecule step by step.

### Step 1: Analyze \( H_2O \)
1. **Identify the central atom**: The central atom in water is oxygen (O).
2. **Count the valence electrons**: Oxygen has 6 valence electrons.
3. **Determine bonding**: In \( H_2O \), oxygen forms two single bonds with two hydrogen atoms.
4. **Calculate lone pairs**:
- Total valence electrons = 6
- Electrons used in bonding = 2 (for each bond with H, total 2 bonds)
- Remaining electrons = 6 - 2 = 4
- Lone pairs = 4 electrons / 2 = 2 lone pairs.

### Step 2: Analyze \( SnCl_2 \)
1. **Identify the central atom**: The central atom is tin (Sn).
2. **Count the valence electrons**: Tin is in group 14 and has 4 valence electrons.
3. **Determine bonding**: In \( SnCl_2 \), tin forms two single bonds with two chlorine atoms.
4. **Calculate lone pairs**:
- Total valence electrons = 4
- Electrons used in bonding = 2 (for each bond with Cl, total 2 bonds)
- Remaining electrons = 4 - 2 = 2
- Lone pairs = 2 electrons / 2 = 1 lone pair.

### Step 3: Analyze \( PCl_3 \)
1. **Identify the central atom**: The central atom is phosphorus (P).
2. **Count the valence electrons**: Phosphorus is in group 15 and has 5 valence electrons.
3. **Determine bonding**: In \( PCl_3 \), phosphorus forms three single bonds with three chlorine atoms.
4. **Calculate lone pairs**:
- Total valence electrons = 5
- Electrons used in bonding = 3 (for each bond with Cl, total 3 bonds)
- Remaining electrons = 5 - 3 = 2
- Lone pairs = 2 electrons / 2 = 1 lone pair.

### Step 4: Analyze \( XeF_2 \)
1. **Identify the central atom**: The central atom is xenon (Xe).
2. **Count the valence electrons**: Xenon is in group 18 and has 8 valence electrons.
3. **Determine bonding**: In \( XeF_2 \), xenon forms two single bonds with two fluorine atoms.
4. **Calculate lone pairs**:
- Total valence electrons = 8
- Electrons used in bonding = 2 (for each bond with F, total 2 bonds)
- Remaining electrons = 8 - 2 = 6
- Lone pairs = 6 electrons / 2 = 3 lone pairs.

### Summary of Lone Pairs
- \( H_2O \): 2 lone pairs
- \( SnCl_2 \): 1 lone pair
- \( PCl_3 \): 1 lone pair
- \( XeF_2 \): 3 lone pairs

### Final Answer
The number of lone pairs of electrons on the central atom of \( H_2O, SnCl_2, PCl_3, \) and \( XeF_2 \) respectively are: **2, 1, 1, 3**.