The partial pressure of oxygen in a sample of air is 452mmHg and the total...
The partial pressure of oxygen in a sample of air is 452mmHg and the total pressure is 780mmHg. What is the mole fraction of oxygen?
- A) 0.203
- B) 0.579
- C) 2.060
- D) 5.790
Correct Answer: B) 0.579
Explanation
To solve this problem, we need to find the mole fraction of oxygen. The mole fraction is the ratio of the partial pressure of a specific gas to the total pressure of the gas mixture.
The formula for calculating the mole fraction is:
\(X_{O_2} = \frac{P_{O_2}}{P_{total}}\)
Where \(X_{O_2}\) is the mole fraction of oxygen, \(P_{O_2}\) is the partial pressure of oxygen, and \(P_{total}\) is the total pressure of the gas mixture.
Given the partial pressure of oxygen (\(P_{O_2} = 452 mmHg\)) and the total pressure (\(P_{total} = 780 mmHg\)), we can substitute these values into the formula:
\(X_{O_2} = \frac{452}{780}\)
After calculating, we get:
\(X_{O_2} = 0.579\)
Thus, the mole fraction of oxygen is 0.579, which corresponds toOption B.
It's important to understand that the mole fraction is a dimensionless quantity that represents the proportion of one substance in a mixture. In this case, it indicates the proportion of oxygen in the air sample. Mole fraction is useful for calculating various properties of gas mixtures, such as partial pressures and concentration of each component.