Among the following, the molecule with the highest dipole moment is :

Options

A. `CH_(3)Cl`
B. `CH_(2)Cl_(2)`
C. `CHCl_(3)`
D. `C Cl_(4)`

Answer

To determine which molecule among CH3Cl, CH2Cl2, CHCl3, and CCl4 has the highest dipole moment, we can follow these steps:

### Step 1: Identify the Molecular Structures
- **CH3Cl (Chloromethane)**: Contains one carbon atom bonded to three hydrogen atoms and one chlorine atom.
- **CH2Cl2 (Dichloromethane)**: Contains one carbon atom bonded to two hydrogen atoms and two chlorine atoms.
- **CHCl3 (Chloroform)**: Contains one carbon atom bonded to one hydrogen atom and three chlorine atoms.
- **CCl4 (Carbon Tetrachloride)**: Contains one carbon atom bonded to four chlorine atoms.

### Step 2: Determine Hybridization
All four molecules have a central carbon atom with four substituents, leading to:
- **Hybridization**: sp³ for all molecules.
- **Geometry**: Tetrahedral for all molecules.

### Step 3: Analyze Electronegativity and Dipole Moments
- **Electronegativity Values**:
- Carbon (C) = 2.5
- Hydrogen (H) = 2.1
- Chlorine (Cl) = 3.0

- **Dipole Moment Calculation**: The dipole moment is determined by the difference in electronegativity between the bonded atoms and the geometry of the molecule.

### Step 4: Assess Each Molecule
1. **CH3Cl**:
- Dipole moments from C-Cl and C-H bonds. The dipole moments from C-Cl (Cl is more electronegative) will add up in the same direction, resulting in a net dipole moment.

2. **CH2Cl2**:
- Two C-Cl bonds and two C-H bonds. The dipole moments from C-Cl will partially cancel the C-H dipoles, resulting in a lower net dipole moment compared to CH3Cl.

3. **CHCl3**:
- Three C-Cl bonds and one C-H bond. The C-Cl dipoles will again partially cancel each other, resulting in a net dipole moment lower than CH3Cl.

4. **CCl4**:
- Four C-Cl bonds. The dipole moments from each C-Cl bond will cancel each other out due to symmetry, resulting in a net dipole moment of zero.

### Step 5: Compare the Dipole Moments
- **Dipole Moment Values** (approximate):
- CH3Cl: 1.94 D
- CH2Cl2: 1.60 D
- CHCl3: 1.03 D
- CCl4: 0 D

### Conclusion
The molecule with the highest dipole moment is **CH3Cl** with a dipole moment of 1.94 D.

### Final Answer
**The molecule with the highest dipole moment is CH3Cl.**

---