Answer:
PV = V (1.2 n. 0821) (298) = 123 mols 2.
Step-by-step explanation:
We need to use the ideal gas law for this problem, which states that:
PV=nRT
P is pressure in atmospheric pressures (in this case)
V is volume in liters (in this case)
n is moles of the substance
R is the gas constant (for this case, we use 0.082l atm mol−1K−1)
T is the temperature in Kelvin (as always)
Plugging in the known values, V=2.5l, P=1.2atm, T=298K, we get
n=PVRT=1.2⋅2.5298⋅0.082≈0.122 moles
So, there will be 0.122 moles of oxygen gas.