Na2O
M=2.23+16=62----->1mol Na2O=62 g
raport atomic=r.a.=2Na:1O=2:1
raport de masa=r.m.=2ANa:AO=2.23:16=46:16=23:8 s-a simplificat cu 2
Concentratie procentuala
M=46+16=62
62 g Na2O---------46 g Na------------16g O
100 gNa2O---------------Xg Na-----------Yg O
X=100.46:62=
Y=100.16:62=