Structure of `TeCl_4` is

Options

A. Octahedral
B. Square planar
C. Trigonal bipyramidal
D. Tetrahedral

Explanation

To determine the structure of tellurium tetrachloride (TeCl₄), we can follow these steps:

### Step 1: Identify the central atom and its valence electrons
- The central atom in TeCl₄ is tellurium (Te).
- Tellurium is in Group 16 of the periodic table and has 6 valence electrons.

**Hint:** Remember that elements in Group 16 have 6 valence electrons.

### Step 2: Count the number of chlorine atoms and their contribution
- There are 4 chlorine (Cl) atoms in TeCl₄.
- Each chlorine atom contributes 1 electron for bonding, leading to a total of 4 electrons from the 4 Cl atoms.

**Hint:** Each halogen (like Cl) typically forms one bond.

### Step 3: Calculate the total number of electrons around the central atom
- Total electrons around Te = Valence electrons of Te + Electrons from Cl atoms = 6 (from Te) + 4 (from 4 Cl) = 10 electrons.

**Hint:** Combine the valence electrons of the central atom with the bonding electrons from surrounding atoms.

### Step 4: Determine the number of lone pairs on the central atom
- Since Te has 10 electrons and forms 4 bonds with Cl, we can calculate the number of lone pairs:
- Total pairs of electrons = 10 / 2 = 5 pairs.
- 4 pairs are used for bonding with Cl, leaving 1 lone pair.

**Hint:** Each bond uses a pair of electrons, so count how many pairs are left after bonding.

### Step 5: Determine the hybridization
- The hybridization can be determined using the formula:
- Hybridization index = Number of sigma bonds + Number of lone pairs.
- Here, we have 4 sigma bonds (from 4 Te-Cl bonds) and 1 lone pair.
- Hybridization index = 4 + 1 = 5.

**Hint:** Hybridization index helps in determining the type of hybridization.

### Step 6: Identify the hybridization type
- A hybridization index of 5 corresponds to sp³d hybridization.

**Hint:** Different hybridization types correspond to different geometries.

### Step 7: Determine the molecular geometry and shape
- With sp³d hybridization, the geometry is trigonal bipyramidal.
- However, due to the presence of one lone pair, the shape of the molecule is altered to a seesaw shape.

**Hint:** The presence of lone pairs can distort the molecular shape from the ideal geometry.

### Conclusion
- The structure of TeCl₄ is trigonal bipyramidal in geometry, but its molecular shape is seesaw due to the lone pair on the central atom.

**Final Answer:** The structure of TeCl₄ is trigonal bipyramidal, and its molecular shape is seesaw.