1 CH4-.> RAPORT ATOMIC 1C:4H
RAPORT MASIC 1x12gC:4gH= 3:1
IN 16g CH4 .....12gC......4gH
100 x y CALCULEAZA PROCENTELE x si y
2 100g oxid contine 72,73gO
44g m=32g==> n=32g/16g/mol==> 2 molO ===> XO2
MASA elementului x; 44g oxid-32g O=12gX===> C ===. CO2
3.RAPORTUL DE MASA: 43,39gNa:11,32gC:44,29gO
RAPORTUL DE ATOMI: 43,39/12: 11,32/12: 44,29/16= 1,88:0,94:2,77
impartind la cel mai mic: 2:1:3-===>Na2CO3