1. Ideal Gas Law

The ideal gas law is the foundation for this calculation:

PV = nRT

Where:

* P = Pressure (in atmospheres)

* V = Volume (in liters)

* n = Number of moles

* R = Ideal gas constant (0.0821 L·atm/mol·K)

* T = Temperature (in Kelvin)

2. Plug in the Values

* P = 1.3 atm

* n = 2 moles

* R = 0.0821 L·atm/mol·K

* T = 300 K

3. Solve for Volume (V)

V = (nRT) / P

V = (2 moles * 0.0821 L·atm/mol·K * 300 K) / 1.3 atm

V ≈ 38.0 L

Therefore, the volume of oxygen occupied by 2 moles at 1.3 ATM pressure and 300K is approximately 38.0 liters.