m= nxM
mCu=0,2molx64g/mol= 12,8g
mS= 0,2molx32g/mol= 6,4g
masa totala=19,2g
in 19,2g amestec.......12,8gCu.......6,4gS
100g.........................x.....................y
x= 100x12,8/19,2=......................
y=100x6,4/19,2=........................calculeaza !!!!
calculeaza x si y