Hydrogen and oxygen gas are mixed in a 7.75 L flask at 65oC and contains 0.482 g of hydrogen and 4.98 g of oxygen. What is the partial pressure of oxygen in the flask?
To find the partial pressure of oxygen in the flask, we first need to calculate the moles of each gas present in the flask.
1. Calculate moles of hydrogen:
moles of hydrogen = mass of hydrogen / molar mass of hydrogen
moles of hydrogen = 0.482 g / 2.016 g/mol = 0.239 moles
2. Calculate moles of oxygen:
moles of oxygen = mass of oxygen / molar mass of oxygen
moles of oxygen = 4.98 g / 32.00 g/mol = 0.156 moles
3. Now, we can use the ideal gas law to calculate the partial pressure of oxygen:
PV = nRT
where:
P = partial pressure of oxygen
V = volume of the flask in liters (7.75 L)
n = moles of oxygen (0.156 moles)
R = ideal gas constant (0.0821 L.atm/mol.K)
T = temperature in Kelvin (65 + 273 = 338 K)
Substitute the values into the equation:
P * 7.75 = 0.156 * 0.0821 * 338
P * 7.75 = 4.1888
P = 4.1888 / 7.75
P ≈ 0.54 atm
Therefore, the partial pressure of oxygen in the flask is approximately 0.54 atm.