My attempt at interpreting that question, is you are asking about buoyancy.
If so, let's see if I can confuse the matter for you.
1 gallon of distilled water is 8 pounds.
A gallon is 231 cubic inches.
A cubic foot is 12 x 12 x 12 = 1728 cubic inches
1728 / 231 = 7.48 gallons per cubic foot
so, 7.48 x 8 = 59.84 lbs of distilled water in one cubic foot.
Sea water, because of the dissolved minerals, is about 64 lbs per cubic foot.
So, 1 cubic foot of trapped air space in a hull produces about 60 to 64 lbs of buoyancy,
depending on whether your boat is floating in a lake or the ocean.