The number of moles for co2=mass(g)/molar mass
n=.22/44=.005 mole of CO2
from the equation we see the relationship between the moles of co2 and O2 and we find that they have the same number of moles
So we need .005mole of O2
Multiple the number of moles with avogadro’s number to know the number of O2molecules
.005x6.022 x10^23