Identfity molecular solide, covalent solid, ionic solid: `P_(4)(s), S_(8)(s), SiC (s), Al_(2)O_(3)(s), He(s), Al_(2)Cl_(6)(s)`.

Explanation

To classify the given solids into molecular solids, covalent solids, and ionic solids, we will analyze each substance based on their structure and bonding characteristics.

### Step-by-Step Solution:

1. **Identify Phosphorus (P₄)**:
- Phosphorus exists as P₄, which is a molecular form. It has a simple structure and consists of discrete molecules.
- **Classification**: Molecular Solid.

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