Which of the following molecule is planar as well as polar :

Options

A. `PCl_(3)`
B. `SF_(4)`
C. `ClF_(3)`
D. None of these

Answer

To determine which of the following molecules is planar as well as polar, we will analyze each molecule step by step. The molecules in question are PCl3, SF4, and ClF3.

### Step 1: Analyze PCl3 (Phosphorus Trichloride)
1. **Draw the Lewis Structure**: PCl3 has a phosphorus atom bonded to three chlorine atoms.
2. **Determine the Geometry**: The geometry of PCl3 is trigonal pyramidal due to the presence of one lone pair of electrons on phosphorus.
3. **Check Planarity**: A trigonal pyramidal structure is not planar because the lone pair pushes the chlorine atoms down, creating a three-dimensional shape.
4. **Check Polarity**: However, PCl3 is polar due to the difference in electronegativity between phosphorus and chlorine, leading to a net dipole moment.

**Conclusion for PCl3**: Not planar, but polar.

### Step 2: Analyze SF4 (Sulfur Tetrafluoride)
1. **Draw the Lewis Structure**: SF4 consists of a sulfur atom bonded to four fluorine atoms.
2. **Determine the Geometry**: The geometry of SF4 is seesaw due to one lone pair of electrons on sulfur.
3. **Check Planarity**: In the seesaw structure, two fluorine atoms are in the equatorial plane, while one is above and one is below the plane. Therefore, SF4 is not planar.
4. **Check Polarity**: The molecule is polar because of the electronegativity difference between sulfur and fluorine, leading to an asymmetric charge distribution.

**Conclusion for SF4**: Not planar, but polar.

### Step 3: Analyze ClF3 (Chlorine Trifluoride)
1. **Draw the Lewis Structure**: ClF3 consists of a chlorine atom bonded to three fluorine atoms.
2. **Determine the Geometry**: The geometry of ClF3 is T-shaped due to the presence of two lone pairs of electrons on chlorine.
3. **Check Planarity**: The T-shaped structure is not planar because the lone pairs occupy positions above and below the plane formed by the three fluorine atoms.
4. **Check Polarity**: ClF3 is polar due to the difference in electronegativity between chlorine and fluorine, resulting in a net dipole moment.

**Conclusion for ClF3**: Not planar, but polar.

### Final Conclusion
None of the given molecules (PCl3, SF4, ClF3) are planar while being polar. Therefore, the answer to the question is **none of these**.