The weight of 12 fluid ounces depends on the density of the substance. Twelve fluid ounces of milk weighs 33.94 ounces, but 12 fluid ounces of pure water weighs 12.52 ounces. Salt water weighs 12.84 ounces due to its lower density.
The same 12 fluid ounces of granulated sugar weighs 10.63 ounces, while 12 fluid ounces of roasted coffee beans weigh only 5.41 ounces. The contents of a 12-fluid-ounce can of soda weigh about 7.64 ounces.
A fluid ounce is equal to 2 tablespoons or 0.03 liter. Twelve fluid ounces are therefore equivalent in volume to 24 teaspoons or 0.35 liter.