You're going to need to be more specific! The weight of a gallon of alcohol depends on the type of alcohol:

* Pure ethanol (ethyl alcohol): A gallon of pure ethanol weighs about 6.6 pounds.

* Isopropyl alcohol (rubbing alcohol): A gallon of isopropyl alcohol weighs about 6.7 pounds.

* Other alcohols: The weight of a gallon of other alcohols will vary depending on their density.

Important Note: These are approximate weights. The actual weight will depend on the specific type of alcohol, its purity, and the temperature.

If you can tell me what kind of alcohol you're interested in, I can give you a more accurate answer.