Molecules with see-saw shape are

Options

A. `SF_(4)`
B. `XeOF_(4)`
C. `XeO_(2)F_(2)`
D. `HgCl_(2)`

Answer

To determine which molecules have a seesaw shape, we will analyze the given options based on their hybridization and molecular geometry.

### Step-by-Step Solution:

1. **Identify the Molecules and Their Central Atoms:**
- **Option 1:** SF4 (Sulfur tetrafluoride)
- **Option 2:** XeOF4 (Xenon oxyfluoride)
- **Option 3:** XeO2F2 (Xenon dioxydifluoride)
- **Option 4:** HgCl2 (Mercury dichloride)

2. **Calculate Hybridization for Each Molecule:**
- **SF4:**
- Valence electrons of Sulfur (S) = 6
- Number of monovalent atoms (F) = 4
- Charge = 0
- Hybridization = \( \frac{1}{2} \times (6 + 4 + 0) = \frac{10}{2} = 5 \) → sp³d
- Geometry = Trigonal bipyramidal
- Bond pairs = 4, Lone pairs = 1 → Seesaw shape

- **XeOF4:**
- Valence electrons of Xenon (Xe) = 8
- Number of monovalent atoms (O + F) = 4
- Charge = 0
- Hybridization = \( \frac{1}{2} \times (8 + 4 + 0) = \frac{12}{2} = 6 \) → sp³d²
- Geometry = Octahedral
- Bond pairs = 5, Lone pairs = 1 → Square pyramidal shape (not seesaw)

- **XeO2F2:**
- Valence electrons of Xenon (Xe) = 8
- Number of monovalent atoms (O + F) = 2
- Charge = 0
- Hybridization = \( \frac{1}{2} \times (8 + 2 + 0) = \frac{10}{2} = 5 \) → sp³d
- Geometry = Trigonal bipyramidal
- Bond pairs = 4, Lone pairs = 1 → Seesaw shape

- **HgCl2:**
- Valence electrons of Mercury (Hg) = 2
- Number of monovalent atoms (Cl) = 2
- Charge = 0
- Hybridization = \( \frac{1}{2} \times (2 + 2 + 0) = \frac{4}{2} = 2 \) → sp
- Geometry = Linear
- Bond pairs = 2, Lone pairs = 0 → Linear shape

3. **Conclusion:**
- The molecules with seesaw shape are **SF4** and **XeO2F2**.
- The correct options are **Option 1 (SF4)** and **Option 3 (XeO2F2)**.

### Final Answer:
The molecules with seesaw shape are **SF4** and **XeO2F2**.