At a pressure of 2.00 atm, a sample of air consists of 0.20 moles of nitrogen, 0.65 moles of oxygen and 0.15 moles of argon. What is the partial pressure of the oxygen?
To find the partial pressure of oxygen, we need to determine the mole fraction of oxygen and then multiply it by the total pressure.
Step 1: Calculate the total number of moles:
Total moles = moles of nitrogen + moles of oxygen + moles of argon
Total moles = 0.20 moles + 0.65 moles + 0.15 moles
Total moles = 1.00 moles
Step 2: Calculate the mole fraction of oxygen:
Mole fraction of oxygen = moles of oxygen / total moles
Mole fraction of oxygen = 0.65 moles / 1.00 moles
Mole fraction of oxygen = 0.65
Step 3: Calculate the partial pressure of oxygen:
Partial pressure of oxygen = Mole fraction of oxygen * Total pressure
Partial pressure of oxygen = 0.65 * 2.00 atm
Partial pressure of oxygen = 1.30 atm
Therefore, the partial pressure of oxygen is 1.30 atm.