Question

helium is mixed with oxygen gas for deep - sea divers. calculate the percent by volume of oxygen gas in the mixture if the diver has to submerge to a depth where the total pressure is 4.5 atm. the partial pressure of oxygen is maintained at 0.20 atm at this depth. round your answer to 2 significant digits.

Explanation:

Step1: Recall Dalton's Law

Partial pressure = mole fraction × total pressure. Mole fraction = volume % / 100.

Step2: Rearrange for volume %

Volume % = (Partial pressure of O₂ / Total pressure) × 100

Step3: Substitute values

Volume % = (0.20 atm / 4.5 atm) × 100 ≈ 4.444...

Step4: Round to 2 sig figs

4.444... ≈ 4.4

Answer:

4.4