The hybridisation fo `BeCl_2` in solid state and above 1200 K is respectively

Options

A. `sp^3, sp^3`
B. `sp^3, sp^2`
C. `sp^2, sp^2`
D. `sp^3, sp`

Answer

To determine the hybridization of BeCl₂ in the solid state and above 1200 K, we can follow these steps:

### Step 1: Analyze the structure of BeCl₂ in the solid state
- In the solid state, BeCl₂ exists as a polymer chain structure. This means that the beryllium atoms are linked together through chlorine atoms, forming a continuous chain.
- The beryllium atom in this structure is surrounded by four pairs of electrons (two bonding pairs from the two Cl atoms and two lone pairs), which leads to an sp³ hybridization.

### Step 2: Identify the hybridization above 1200 K
- When the temperature rises above 1200 K, BeCl₂ transitions from a solid to a gaseous state, where it exists as discrete molecules rather than a polymer.
- In this gaseous state, the BeCl₂ molecule is linear, with the beryllium atom in the center and the two chlorine atoms on either side.
- For a linear molecule, the hybridization of the central atom (beryllium) is sp.

### Conclusion
- Therefore, the hybridization of BeCl₂ in the solid state is sp³, and above 1200 K, it is sp. Thus, the final answer is sp³ and sp.

### Final Answer
The hybridization of BeCl₂ in solid state and above 1200 K is respectively sp³ and sp.

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