Which among the following molecules is not flat?

Options

A. 1. `C_6H_6`
B. 2. `C_2H_4`
C. 3. `SO_3`
D. 4. `C_2H_6`

Explanation

To determine which among the given molecules is not flat, we will analyze the hybridization and geometry of each molecule:

1. **C6H6 (Benzene)**:
- Structure: Benzene has a hexagonal ring structure with alternating double bonds.
- Hybridization: Each carbon atom in benzene is sp² hybridized.
- Geometry: The sp² hybridization leads to a planar structure.
- Conclusion: Benzene is a planar molecule.

2. **C2H4 (Ethene)**:
- Structure: Ethene has a double bond between the two carbon atoms, represented as C=C, with each carbon bonded to two hydrogen atoms.
- Hybridization: Each carbon atom is sp² hybridized.
- Geometry: The sp² hybridization results in a planar structure.
- Conclusion: Ethene is also a planar molecule.

3. **SO3 (Sulfur Trioxide)**:
- Structure: Sulfur trioxide has a central sulfur atom bonded to three oxygen atoms, typically represented with double bonds (O=S=O).
- Hybridization: The sulfur atom is sp² hybridized.
- Geometry: The sp² hybridization gives a planar structure.
- Conclusion: Sulfur trioxide is planar as well.

4. **C2H6 (Ethane)**:
- Structure: Ethane consists of two carbon atoms connected by a single bond, with each carbon atom bonded to three hydrogen atoms (C-C).
- Hybridization: Each carbon atom is sp³ hybridized.
- Geometry: The sp³ hybridization results in a tetrahedral geometry around each carbon atom, which is not planar.
- Conclusion: Ethane is a non-planar molecule.

**Final Answer**: The molecule that is not flat among the given options is **C2H6 (Ethane)**.

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