The number of lone pair of electrons on the central atoms of `H_2O, 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 atoms of \( H_2O \), \( SnCl_2 \), \( PCl_3 \), and \( XeF_2 \), we will analyze each molecule step by step.

### Step 1: Analyze \( H_2O \)
- The central atom in \( H_2O \) is oxygen (O).
- Oxygen has 6 valence electrons.
- It forms 2 bonds with hydrogen atoms, using 2 of its valence electrons.
- This leaves 4 electrons, which are in the form of 2 lone pairs.

**Lone pairs in \( H_2O \): 2**

### Step 2: Analyze \( SnCl_2 \)
- The central atom in \( SnCl_2 \) is tin (Sn).
- Tin has 4 valence electrons.
- It forms 2 bonds with chlorine atoms, using 2 of its valence electrons.
- This leaves 2 electrons, which form 1 lone pair.

**Lone pairs in \( SnCl_2 \): 1**

### Step 3: Analyze \( PCl_3 \)
- The central atom in \( PCl_3 \) is phosphorus (P).
- Phosphorus has 5 valence electrons.
- It forms 3 bonds with chlorine atoms, using 3 of its valence electrons.
- This leaves 2 electrons, which form 1 lone pair.

**Lone pairs in \( PCl_3 \): 1**

### Step 4: Analyze \( XeF_2 \)
- The central atom in \( XeF_2 \) is xenon (Xe).
- Xenon has 8 valence electrons.
- It forms 2 bonds with fluorine atoms, using 2 of its valence electrons.
- This leaves 6 electrons, which can be arranged as 3 lone pairs.

**Lone pairs in \( XeF_2 \): 3**

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

Thus, the final answer is: **2, 1, 1, 3**.

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