does a fluid ounce of water weigh an ounce
Fluid ounce The fluid ounce is distinct from the ounce as a unit of weight or mass, although it is sometimes referred to simply as an "ounce" where context makes the meaning clear, such as ounces in a bottle.
Liquid air Liquid air has a density of approximately 870Â kg/m3 (0.87 g/cm3), though the density may vary depending on the elemental composition of the air. Since dry gaseous air contains approximately 78% nitrogen, 21% oxygen, and 1% argon, the density of liquid air at standard composition is calculated by the percentage of the components and their respective liquid densities (see liquid nitrogen and liquid oxygen). Although air contains trace amounts of carbon dioxide (about 0.040%), this gas sublimates (transfers directly between gas and solid, and therefore does not exist as a liquid) at pressures less than 5.1 atmospheres.