Which of the following statement about anhydrous aluminium chloride is correct?

Options

A. It fumes is moist air.
B. It exists as dimer both in the vapour state below `350^(@)C` and in non - polar solvents
C. It is preapared by heating `Al_(2)O_(3)` in a stream of sulphur chloride `(S_(2)Cl_(2))` vapor and chlorine.
D. All of these

Answer

To determine which statement about anhydrous aluminum chloride (AlCl3) is correct, we can analyze the options provided based on the information given in the video transcript.

### Step-by-Step Solution:

1. **Understanding Anhydrous Aluminum Chloride**:
Anhydrous aluminum chloride (AlCl3) is a chemical compound that is known for its properties in various states and reactions.

2. **Statement Analysis**:
- **Statement A**: "It fumes in moist air."
- Anhydrous aluminum chloride reacts with moisture in the air, producing hydrochloric acid (HCl) and aluminum hydroxide. This reaction leads to the formation of white fumes, confirming that this statement is correct.

- **Statement B**: "It exists as a dimer both in vapor state below 350 degrees Celsius and in non-polar solvents."
- In the vapor state and in non-polar solvents, AlCl3 indeed exists as a dimer (Al2Cl6). This is due to the formation of bridging chlorine atoms between two aluminum centers, which is a characteristic of its molecular structure. This statement is also correct.

- **Statement C**: "It is prepared by heating Al2O3 in the stream of sulfur chloride, vapor, and chlorine."
- The preparation of AlCl3 can be done by reacting aluminum oxide (Al2O3) with sulfur chloride (SO2Cl2) and chlorine gas (Cl2). The balanced reaction is indeed correct, confirming that this statement is also correct.

3. **Conclusion**:
Since all the statements about anhydrous aluminum chloride are correct, the answer is that **all of these statements are correct**.

### Final Answer:
All of the statements regarding anhydrous aluminum chloride are correct.

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