-masa molara a substantei
M(miu)=( 12gC+ 2X16gO)/mol= 44g/mol
-cantitatea,adica numar de moli
n(niu)= V/V,m= V,l/22,4 l/mol----> n=5,6 l/22,4l/mol= 0,25mol CO2
-numar de molecule
se stie 1mol molec. ....contine 6,023x10²³molec.(numarul lui Avogadro)
0,25mol...........................x=1,5x10²³molec.