For divers going to great depths, the composition of the air in the tank must be modified. The ideal composition is to have approximately the same number of O2 molecules per unit volume as in surface air (to avoid oxygen poisoning), and to use helium instead of nitrogen for the remainder of the gas (to avoid nitrogen narcosis, which results from nitrogen dissolving in the bloodstream). Of the molecules in dry surface air, 78.0% are N2, 21.0% are O2, and 1.00% are Ar. (Assume that the density of seawater is 1025 kg/m3 and the temperature is 20.0°C.) Density of dry air at 20.0°C is 1.20 kg/m3. Molar mass of N2 is 14.007 g/mol, O2 is 15.999 g/mol, and Ar is 39.948 g/mol. For a diver going to a depth of 141 m, what percentage of the gas molecules in the tank should be O2?

For divers going to great depths, the composition of the air in the tank must be modified. The ideal composition is to have approximately the same number of O2 molecules per unit volume as in surface air (to avoid oxygen poisoning), and to use helium instead of nitrogen for the remainder of the gas (to avoid nitrogen narcosis, which results from nitrogen dissolving in the bloodstream). Of the molecules in dry surface air, 78.0% are N2, 21.0% are O2, and 1.00% are Ar. (Assume that the density of seawater is 1025 kg/m3 and the temperature is 20.0°C.) Density of dry air at 20.0°C is 1.20 kg/m3. Molar mass of N2 is 14.007 g/mol, O2 is 15.999 g/mol, and Ar is 39.948 g/mol. For a diver going to a depth of 141 m, what percentage of the gas molecules in the tank should be O2?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter19: Temperature, Thermal Expansion And Gas Laws

Section: Chapter Questions

Problem 61PQ

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