How many moles of oxygen will occupy a volume of 2.50 at 1.20 atm and 25.0 c?

The number of mol of oxygen is 0, 123

Explanation:

We use the formula PV=nRT. We convert the temperature in Celsius into Kelvin. 0°C=273 K---> 25°C=273+25 = 298K

PV=nRT---> n = (PV) / (RT)

n = (1,20 atm x2,50 L) / (0,082 l atm / K mol x 298K)

n=0,122769684 mol