How many liters of oxygen at stp are needed to react with 5.2 * 10 to the 22nd power molecules of hydrogen sulfide?
5.2E+22 molecules of H2S=(5.2E+22)/(6.022E+23)=0.0864moles
H2S + 2O2==>H2SO4
from equation 1mole of H2S reacts=2moles of Oxygen
so 0.0864moles of H2S will react=0.173moles of Oxygen
Since at STP 1mole of O2=22.14L