What is the structure of `BeCI_(2)` molecule in gaseous and solid state?

Explanation

To determine the structure of the BeCl₂ molecule in both gaseous and solid states, we can analyze the bonding and arrangement of atoms in each state.

### Step 1: Structure of BeCl₂ in Solid State
1. **Polymeric Structure**: In the solid state, BeCl₂ exists as a polymeric structure. This means that the molecules are linked together in a continuous chain.
2. **Tetrahedral Geometry**: The beryllium (Be) atom is surrounded by four chlorine (Cl) atoms, forming a tetrahedral shape.
3. **Bond Types**: Out of the four bonds, two are covalent bonds and two are coordinate bonds. The coordinate bonds are formed when the beryllium atom accepts electron pairs from the chlorine atoms.
4. **Visualization**:
- Draw a central Be atom.
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