A heliox deep-sea diving mixture contains 2.0 g of oxygen to every 98.0 g of helium.
What is the partial pressure of oxygen when this mixture is delivered at a total pressure of 9.3 atm?
To calculate the partial pressure of oxygen in the heliox diving mixture, we need to first determine the moles of oxygen and helium present.
To determine the moles of oxygen, we can use the given mass of oxygen (2.0 g) and the molar mass of oxygen (32.0 g/mol).
Moles of oxygen = mass of oxygen / molar mass of oxygen
= 2.0 g / 32.0 g/mol
= 0.0625 mol
To determine the moles of helium, we can use the given mass of helium (98.0 g) and the molar mass of helium (4.0 g/mol).
Moles of helium = mass of helium / molar mass of helium
= 98.0 g / 4.0 g/mol
= 24.5 mol
Now, we need to calculate the mole fraction of oxygen in the mixture.
Mole fraction of oxygen = moles of oxygen / total moles
= 0.0625 mol / (0.0625 mol + 24.5 mol)
≈ 0.002548
Next, we can use the ideal gas law to calculate the partial pressure of oxygen.
Partial pressure of oxygen = mole fraction of oxygen × total pressure
= 0.002548 × 9.3 atm
≈ 0.0237 atm
Therefore, the partial pressure of oxygen in the heliox diving mixture when delivered at a total pressure of 9.3 atm is approximately 0.0237 atm.
To find the partial pressure of oxygen in the heliox mixture, we can use Dalton's law of partial pressures, which states that the total pressure of a gas mixture is equal to the sum of the partial pressures of each component gas.
First, we need to find the mole fraction of oxygen in the mixture. The mole fraction is the ratio of moles of a specific gas to the total moles of all gases in the mixture.
The molar mass of oxygen (O2) is 32 g/mol, and the molar mass of helium (He) is 4 g/mol.
Calculating the moles of oxygen:
moles of oxygen = mass of oxygen / molar mass of oxygen
= 2.0 g / 32 g/mol
= 0.0625 mol
Calculating the moles of helium:
moles of helium = mass of helium / molar mass of helium
= 98.0 g / 4 g/mol
= 24.5 mol
Now we can find the mole fraction of oxygen:
mole fraction of oxygen = moles of oxygen / (moles of oxygen + moles of helium)
= 0.0625 mol / (0.0625 mol + 24.5 mol)
≈ 0.00253
Next, we can use the mole fraction of oxygen to find its partial pressure.
partial pressure of oxygen = mole fraction of oxygen * total pressure
= 0.00253 * 9.3 atm
≈ 0.0235 atm
Therefore, the partial pressure of oxygen in the heliox mixture is approximately 0.0235 atm.
find moles of each. Then add them to get total moles.
pressureO2= molesO2/totalmoles * 9.3atm
pressureHe=molesH2/totalmoles*9.3 atm
http://en.wikipedia.org/wiki/Dalton%27s_law