Which of the following pair is having planar structure

Options

A. `SF_(4),XeF_(4)`
B. `H_(3)O^(+),SO_(2)`
C. `BF_(3),XeOF_(2)`
D. `XeF_(4),NO_(3)^(-)`

Answer

To determine which of the given pairs has a planar structure, we can analyze the molecular geometry of each option based on their valence electrons and hybridization.

### Step-by-Step Solution:

1. **Analyze Option 1: SF4 and XeF4**
- **SF4 (Sulfur Tetrafluoride)**:
- Sulfur has 6 valence electrons, and each fluorine has 7 (4 fluorines contribute 28 electrons).
- Total = 6 + 28 = 34 electrons.
- Dividing by 2 gives us 17 pairs. This means there are 4 bond pairs and 1 lone pair (34 - 32 = 2 electrons, which corresponds to 1 lone pair).
- Geometry: The arrangement is trigonal bipyramidal with one lone pair, leading to a seesaw shape, which is not planar.
- **XeF4 (Xenon Tetrafluoride)**:
- Xenon has 8 valence electrons and each fluorine has 7 (4 fluorines contribute 28 electrons).
- Total = 8 + 28 = 36 electrons.
- Dividing by 2 gives us 18 pairs. This means there are 4 bond pairs and 2 lone pairs (36 - 32 = 4 electrons, which corresponds to 2 lone pairs).
- Geometry: The arrangement is octahedral, and with 2 lone pairs, the shape is square planar, which is planar.

**Conclusion for Option 1**: Not both are planar (only XeF4 is planar).

2. **Analyze Option 2: H3O+ and SO2**
- **H3O+ (Hydronium Ion)**:
- Oxygen has 6 valence electrons, and each hydrogen has 1 (3 hydrogens contribute 3 electrons).
- Total = 6 + 3 - 1 (due to the positive charge) = 8 electrons.
- Dividing by 2 gives us 4 pairs. This means there are 3 bond pairs and 1 lone pair.
- Geometry: The arrangement is tetrahedral with one lone pair, leading to a pyramidal shape, which is not planar.
- **SO2 (Sulfur Dioxide)**:
- Sulfur has 6 valence electrons, and each oxygen has 6 (2 oxygens contribute 12 electrons).
- Total = 6 + 12 = 18 electrons.
- Dividing by 2 gives us 9 pairs. This means there are 2 bond pairs and 1 lone pair.
- Geometry: The arrangement is bent due to the lone pair, which is also not planar.

**Conclusion for Option 2**: Not both are planar.

3. **Analyze Option 3: BF3 and XeOF2**
- **BF3 (Boron Trifluoride)**:
- Boron has 3 valence electrons, and each fluorine has 7 (3 fluorines contribute 21 electrons).
- Total = 3 + 21 = 24 electrons.
- Dividing by 2 gives us 12 pairs. This means there are 3 bond pairs and no lone pairs.
- Geometry: The arrangement is trigonal planar, which is planar.
- **XeOF2 (Xenon Oxyfluoride)**:
- Xenon has 8 valence electrons, oxygen has 6, and each fluorine has 7 (2 fluorines contribute 14 electrons).
- Total = 8 + 6 + 14 = 28 electrons.
- Dividing by 2 gives us 14 pairs. This means there are 2 bond pairs and 2 lone pairs.
- Geometry: The arrangement is trigonal bipyramidal, but with 2 lone pairs, it forms a T-shaped structure, which is planar.

**Conclusion for Option 3**: Both are planar.

4. **Analyze Option 4: XeF4 and Nitrate Ion (NO3-)**
- **XeF4 (Xenon Tetrafluoride)**: As analyzed earlier, it is square planar.
- **Nitrate Ion (NO3-)**:
- Nitrogen has 5 valence electrons, and each oxygen has 6 (3 oxygens contribute 18 electrons).
- Total = 5 + 18 + 1 (due to the negative charge) = 24 electrons.
- Dividing by 2 gives us 12 pairs. This means there are 3 bond pairs and no lone pairs.
- Geometry: The arrangement is trigonal planar, which is planar.

**Conclusion for Option 4**: Both are planar.

### Final Answer:
The pair that has a planar structure is **Option 4: XeF4 and Nitrate Ion (NO3-)**.