An "empty" container is not really empty if it contains air. How may moles of oxygen are in an "empty" two-liter cola bottle at atmospheric pressure (1 atm) and room temperature (25∘C)? Assume ideal behavior.

The number of moles present in the container N = 81.56

Explanation:

Pressure = 1 atm = 101325 K pa

Temperature = 298 K

Volume = 0.002

Gas constant for oxygen = = 0.26

From ideal gas equation

P V = m R T -------- (1)

Put all the values in above formula,

101325 × 0.002 = m × 0.26 × 298

⇒ m = 2.61 kg=  2610 gm

This is the mass of the gas.

Now no. of moles of the gas is calculated by

Mass of one mole of oxygen = 32 gm

N =

N = 81.56

These are the number of moles present in the container.