Which of the following is a covalent compound ?

Options

A. `Al_(2)O_(3)`
B. `AlF_(3)`
C. `AlCl_(3)`
D. `Al_(2)(SO_(4))_(3)`

Answer

To determine which of the given compounds is a covalent compound, we will analyze each option based on their bonding characteristics.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds given are Al2O3, AlF3, AlCl3, and Al2(SO4)3.

2. **Analyze Al2O3**:
- Al2O3 is composed of aluminum ions (Al³⁺) and oxide ions (O²⁻).
- The bond formed between these ions is ionic due to the transfer of electrons from aluminum to oxygen.
- **Conclusion**: Al2O3 is an ionic compound.

3. **Analyze AlF3**:
- AlF3 consists of aluminum ions (Al³⁺) and fluoride ions (F⁻).
- Similar to Al2O3, the bond here is also ionic because of the transfer of electrons from aluminum to fluorine.
- **Conclusion**: AlF3 is an ionic compound.

4. **Analyze AlCl3**:
- AlCl3 is made up of aluminum ions (Al³⁺) and chloride ions (Cl⁻).
- Although it can be considered ionic, AlCl3 exhibits covalent characteristics due to the high electronegativity of chlorine, which leads to the sharing of electrons.
- **Conclusion**: AlCl3 is a covalent compound.

5. **Analyze Al2(SO4)3**:
- Al2(SO4)3 consists of aluminum ions (Al³⁺) and sulfate ions (SO4²⁻).
- The bonding in this compound is ionic as it involves the transfer of electrons from aluminum to the sulfate ion.
- **Conclusion**: Al2(SO4)3 is an ionic compound.

6. **Final Answer**:
- The only covalent compound among the options is **AlCl3**.