A molecule possessing dipole moment is

Options

A. `CH_(4)`
B. `H_(2)O`
C. `BF_(3)`
D. `CO_(2)`

Answer

To determine which molecule possesses a dipole moment, we need to analyze the molecular geometry and electronegativity of the atoms involved in each molecule. Here’s a step-by-step solution:

### Step 1: Analyze CH4 (Methane)
- **Structure**: Tetrahedral (C at the center with 4 H atoms)
- **Electronegativity**: Carbon (C) is less electronegative than Hydrogen (H).
- **Dipole Moment**: The dipole moments from each C-H bond point towards carbon, but they are symmetrically arranged.
- **Result**: The dipole moments cancel each other out, resulting in a net dipole moment of zero.

**Hint**: Consider the symmetry of the molecule and the direction of dipole moments.

### Step 2: Analyze H2O (Water)
- **Structure**: Bent (V-shaped) with O at the center and H atoms at an angle.
- **Electronegativity**: Oxygen (O) is more electronegative than Hydrogen (H).
- **Dipole Moment**: The dipole moments from each O-H bond point towards oxygen.
- **Result**: The dipole moments do not cancel due to the bent shape, resulting in a net dipole moment directed towards oxygen.

**Hint**: Look for molecular shapes that prevent dipole cancellation.

### Step 3: Analyze BF3 (Boron Trifluoride)
- **Structure**: Trigonal planar (B at the center with 3 F atoms).
- **Electronegativity**: Fluorine (F) is more electronegative than Boron (B).
- **Dipole Moment**: The dipole moments from each B-F bond point towards fluorine.
- **Result**: The dipole moments are symmetrically arranged and cancel each other out, resulting in a net dipole moment of zero.

**Hint**: Check if the molecule is symmetrical and how the dipole moments align.

### Step 4: Analyze CO2 (Carbon Dioxide)
- **Structure**: Linear (O=C=O).
- **Electronegativity**: Oxygen (O) is more electronegative than Carbon (C).
- **Dipole Moment**: The dipole moments from each C=O bond point towards oxygen.
- **Result**: The dipole moments are equal in magnitude but opposite in direction, resulting in a net dipole moment of zero.

**Hint**: Remember that linear molecules with symmetrical bonds often have zero dipole moments.

### Conclusion
After analyzing all the molecules:
- **CH4**: Zero dipole moment
- **H2O**: Non-zero dipole moment
- **BF3**: Zero dipole moment
- **CO2**: Zero dipole moment

The only molecule that possesses a dipole moment is **H2O**.

**Final Answer**: The molecule possessing a dipole moment is **H2O**.