This question doesn't have a simple answer because the weight of a half gallon depends on what it's filled with!

Here's why:

* Water: A half gallon of pure water weighs about 8.34 pounds.

* Milk: A half gallon of milk will be a little heavier than water due to the milk's fat and solids content, weighing around 8.6 pounds.

* Other Liquids: The weight of other liquids (like juice, oil, etc.) will vary based on their density.

To find out how much a half gallon of *something* weighs, you'll need to know the density of that substance.