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Answer:
446 mmHg
Explanation:
From the question given above, the following data were obtained:
Total pressure (Pₜ) = 871 mmHg
Partial pressure of He (Pₐ) = 281 mmHg
Partial pressure of N₂ (P₆) = 144 mmHg
Partial pressure of O₂ (P꜀) =?
The partial pressure of O₂ can be obtained as follow:
Pₜ = Pₐ + P₆ + P꜀
871 = 281 + 144 + P꜀
871 = 425 + P꜀
Collect like terms
P꜀ = 871 – 425
P꜀ = 446 mmHg
Therefore, the partial pressure of O₂ in the mixture is 446 mmHg