Answer:
The partial pressure of a gas in a mixture can be calculated using the mole fraction of the gas and the total pressure of the mixture. The mole fraction is the ratio of the number of moles of a particular gas to the total number of moles of gas in the mixture.
First, we need to calculate the mole fraction of oxygen in the mixture.
The molar mass of oxygen (O2) is approximately 32.00 g/mol and the molar mass of helium (He) is approximately 4.00 g/mol.
Number of moles of O2 = 2.0 g / 32.00 g/mol = 0.0625 mol
Number of moles of He = 98.0 g / 4.00 g/mol = 24.5 mol
Total moles in the mixture = 0.0625 mol (O2) + 24.5 mol (He) = 24.5625 mol
The mole fraction of O2 (XO2) = 0.0625 mol / 24.5625 mol = 0.00254
Now, we can calculate the partial pressure of oxygen (PO2) using the formula:
PO2 = XO2 * Ptotal
where Ptotal is the total pressure of the gas mixture.
So, PO2 = 0.00254 * 9.5 atm = 0.0241 atm
Expressed to two significant figures, the partial pressure of oxygen when this mixture is delivered at a total pressure of 9.5 atm is 0.024 atm.
Step-by-step explanation: