Which of the following is incorrect statement about `OSF_(4)` ?

Options

A. S atom has `sp^(3) d` hybridization
B. `OSF_(4)` has distorted trigonal-pyramidal shape
C. O atom is present at the equatorial position.
D. There is no lone pair on S.

Answer

To determine the incorrect statement about OSF₄ (Oxy-sulfur tetrafluoride), we can analyze the structure, hybridization, and geometry of the molecule step by step.

### Step 1: Understand the Structure of OSF₄
OSF₄ consists of one sulfur (S) atom, one oxygen (O) atom, and four fluorine (F) atoms. The sulfur atom is the central atom.

### Step 2: Determine the Hybridization
To find the hybridization of the sulfur atom in OSF₄:
- Sulfur has six valence electrons.
- It forms four sigma bonds with the four fluorine atoms and one double bond with the oxygen atom.
- Therefore, the total number of bonding pairs is five (four from F and one from O).
- The hybridization corresponding to five bonding pairs is sp³d.

### Step 3: Analyze the Geometry
The geometry of OSF₄ can be determined based on the hybridization:
- With sp³d hybridization, the molecular geometry is trigonal bipyramidal.
- In this geometry, there are three equatorial positions and two axial positions.

### Step 4: Position of the Oxygen Atom
In the trigonal bipyramidal geometry of OSF₄:
- The oxygen atom is typically placed in one of the equatorial positions due to its double bond with sulfur, which minimizes steric hindrance.

### Step 5: Check for Lone Pairs on Sulfur
- Sulfur has six valence electrons. Four are used for bonding with fluorine atoms, and two are used to form a double bond with oxygen.
- As a result, there are no lone pairs of electrons on the sulfur atom.

### Step 6: Evaluate the Statements
Now, we can evaluate the statements provided in the question:
1. **Sulfur atom has sp³d hybridization.** - This statement is **correct**.
2. **OSF₄ has distorted trigonal pyramidal geometry.** - This statement is **incorrect**; the correct geometry is trigonal bipyramidal.
3. **Oxygen atom is present at the equatorial position.** - This statement is **correct**.
4. **There is no lone pair on sulfur atom.** - This statement is **correct**.

### Conclusion
The incorrect statement about OSF₄ is the second one: "OSF₄ has distorted trigonal pyramidal geometry."

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