Shape of PCl5 molecule is __

Options

A. Tigonal Planar
B. Linear
C. Trigonal bipyramidal
D. Tetrahedral

Answer

To determine the shape of the PCl5 molecule, we can follow these steps:

### Step 1: Determine the Valence Electrons
Phosphorus (P) has 5 valence electrons, and each chlorine (Cl) atom has 7 valence electrons. Since there are 5 chlorine atoms, we can calculate the total number of valence electrons involved in bonding.

**Hint:** Remember that the valence electrons of the central atom (P) are crucial for determining the bonding and shape of the molecule.

### Step 2: Count the Bonds
In PCl5, phosphorus forms 5 single bonds with 5 chlorine atoms. This means that all 5 valence electrons from phosphorus are used to form bonds.

**Hint:** Each bond corresponds to one of the valence electrons from the central atom.

### Step 3: Calculate the Steric Number
The steric number is calculated by adding the number of bonded atoms to the number of lone pairs on the central atom. In this case, there are 5 bonded chlorine atoms and 0 lone pairs on phosphorus.

Steric Number = Number of Bonded Atoms + Number of Lone Pairs
Steric Number = 5 + 0 = 5

**Hint:** The steric number helps in predicting the hybridization and shape of the molecule.

### Step 4: Determine Hybridization
Based on the steric number of 5, the hybridization of phosphorus in PCl5 can be determined. A steric number of 5 corresponds to sp³d hybridization.

**Hint:** Hybridization is a key concept that helps to explain the geometry of the molecule.

### Step 5: Identify the Molecular Shape
With sp³d hybridization and a steric number of 5, the molecular geometry of PCl5 is trigonal bipyramidal. This shape consists of three chlorine atoms in a plane (equatorial position) and two chlorine atoms above and below this plane (axial position).

**Hint:** Visualizing the arrangement of atoms can help in understanding the molecular shape.

### Conclusion
The shape of the PCl5 molecule is **trigonal bipyramidal**.

**Final Answer:** Trigonal bipyramidal