What is the true mass of water weighed at 24°C in the air if the apparent mass is 1.0346 ± 0.0002 g? The density of air is 0.0012 ± 0.0001g/mL and the density of balance weights is 8.0 ± 0.5 g/mL. The uncertainty in the density of water in Table 2-7 is negligible in comparison to the uncertainty in the density of air.