Answer to Question #169063 in General Chemistry for Yori

Question

How many molecules of oxygen are in one breath?

an animal takes a breath with a volume of 5.80 L at standard temperature and pressure. If the air contains 20.9% oxygen.

................O2 molecules

Answer 1

V(O₂)=5.80*0.209=1.212(L)

PV=nRT

n=PV/RT

n=1*1.212/0.082*273.15 =0.054(mol)

N=n*N_a=0.054*6.02•10²³=3.25•10²²

Answer: 3.25•10²² O₂ molecules.