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CHEMISTRY

JAMB 2000 - Question 7

Chemistry 2000 JAMB Past Questions - Question 7: The partial pressure of oxygen in a sample of air is 452 mm Hg and the total pressure is 780 mm Hg. What is the mole fraction of oxygen?

Choose the correct answers from the options given.

The partial pressure of oxygen in a sample of air is 452 mm Hg and the total pressure is 780 mm Hg. What is the mole fraction of oxygen?

A: 0.203

B: 0.579

C: 2.030

D: 5.79

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Correct Answer

Explanation

Mole fraction = 452 = -0.4-13.00 780 = 0.579 mole
To find the mole fraction of oxygen, we can use the formula:

Mole fraction of oxygen = Partial pressure of oxygen / Total pressure

Mole fraction of oxygen = 452 mm Hg / 780 mm Hg ≈ 0.5795

So, the mole fraction of oxygen in the sample of air is approximately 0.5795.