The structure of `IF_5` can be best described

Options

A.
B.
C.
D. None of these

Explanation

To determine the structure of iodine pentafluoride (IF₅), we will follow these steps:

### Step 1: Determine the Valence Electrons
First, we need to find the number of valence electrons for the central atom, iodine (I), and the surrounding atoms, fluorine (F).

- Iodine has 7 valence electrons.
- Each fluorine atom has 1 valence electron, and there are 5 fluorine atoms.

**Calculation:**
- Total valence electrons = Valence electrons of I + (Valence electrons of F × Number of F atoms)
- Total valence electrons = 7 + (1 × 5) = 7 + 5 = 12

### Step 2: Calculate the Hybridization
Next, we will use the formula for hybridization:

\[ \text{Hybridization} = \frac{\text{Valence electrons of central atom} + \text{Monovalent atoms attached}}{2} \]

In our case:
- Valence electrons of iodine = 7
- Monovalent atoms (fluorine) = 5

**Calculation:**
- Hybridization = (7 + 5) / 2 = 12 / 2 = 6

### Step 3: Identify the Hybridization Type
The hybridization of 6 corresponds to \( sp^3d^2 \).

### Step 4: Determine the Molecular Geometry
For \( sp^3d^2 \) hybridization, the geometry is octahedral. However, we need to consider the shape of the molecule, which is influenced by the presence of lone pairs.

### Step 5: Count the Lone Pairs
Iodine has 7 valence electrons, and it forms 5 bonds with fluorine atoms. Thus, the number of electrons used in bonding is 5.

**Calculation:**
- Lone pairs = Total valence electrons - Electrons used in bonding
- Lone pairs = 7 - 5 = 2

### Step 6: Determine the Molecular Shape
In an octahedral arrangement, if there are lone pairs, they will affect the shape. With 2 lone pairs, the shape of the molecule becomes square pyramidal.

### Conclusion
Thus, the structure of IF₅ can be best described as having an octahedral geometry with a square pyramidal shape.

### Final Answer
The structure of IF₅ can be best described as square pyramidal with an octahedral geometry.

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