For the following pattern of hybridization shown by the central atom, `{:(sp,sp^2,sp^3,sp^3d),((1),(2),(3),"(4)"):}` which of the following options represent the correct sequence of hybridisation , i.e according to the sequence mentioned above ?

Options

A. `H_2O,CO_2,BF_3,PCl_5`
B. `CO_2,H_2O,BF_3,PCl_5`
C. `CO_2,BF_3,H_2O,PCl_5`
D. `H_2O,CO_2,PCl_5,BF_3`

Answer

To solve the question regarding the hybridization of the central atom and to determine the correct sequence of hybridization (sp, sp², sp³, sp³d), we will analyze the hybridization of various compounds step by step.

### Step 1: Understanding Hybridization
Hybridization is the concept where atomic orbitals mix to form new hybrid orbitals. The type of hybridization depends on the number of bond pairs and lone pairs around the central atom.

### Step 2: Identify Bond Pairs and Lone Pairs
To determine the hybridization, we need to count the number of bond pairs and lone pairs around the central atom. The general rules are:
- 2 regions of electron density = sp hybridization
- 3 regions of electron density = sp² hybridization
- 4 regions of electron density = sp³ hybridization
- 5 regions of electron density = sp³d hybridization

### Step 3: Analyze Each Compound
1. **Water (H₂O)**
- Valence Electrons: O has 6, H has 1 (2 H atoms) → Total = 6 + 2 = 8
- Bond Pairs: 2 (H-O bonds)
- Lone Pairs: 2 (on O)
- Total Regions: 2 bond pairs + 2 lone pairs = 4 → **Hybridization: sp³**

2. **Carbon Dioxide (CO₂)**
- Valence Electrons: C has 4, O has 6 (2 O atoms) → Total = 4 + 12 = 16
- Bond Pairs: 2 (C=O double bonds, counted as 1 each)
- Lone Pairs: 0
- Total Regions: 2 bond pairs + 0 lone pairs = 2 → **Hybridization: sp**

3. **Boron Trifluoride (BF₃)**
- Valence Electrons: B has 3, F has 7 (3 F atoms) → Total = 3 + 21 = 24
- Bond Pairs: 3 (B-F bonds)
- Lone Pairs: 0
- Total Regions: 3 bond pairs + 0 lone pairs = 3 → **Hybridization: sp²**

4. **Bromine Pentachloride (BrCl₅)**
- Valence Electrons: Br has 7, Cl has 7 (5 Cl atoms) → Total = 7 + 35 = 42
- Bond Pairs: 5 (Br-Cl bonds)
- Lone Pairs: 0
- Total Regions: 5 bond pairs + 0 lone pairs = 5 → **Hybridization: sp³d**

### Step 4: Sequence of Hybridization
Based on the analysis:
- 1. CO₂ → sp
- 2. BF₃ → sp²
- 3. H₂O → sp³
- 4. BrCl₅ → sp³d

### Final Sequence
The correct sequence of hybridization according to the compounds analyzed is:
1. sp (CO₂)
2. sp² (BF₃)
3. sp³ (H₂O)
4. sp³d (BrCl₅)