1.
raport de masa=r.m.
Cu3(PO4)2
r.m.=3.ACu :2AP :8AO=3.64 :2.31 :8.16=192:62:128=96:31:64 ( s-a simplif. cu 2)
AgCl
r.m.=AAg:ACl =108:35,5
NaHCO3
r.m.=ANa :AH: AC:3AO=23:1:12:3.16
NH3
r.m.=AN:3AH=14:3
H3PO4
r.m.=3AH:AP:4.AO=3:31:4.16=3:31:64
2.
MMgCO3=24+12+3.16=84 ----->1molMgCO3=84 g
84g MgCO3------------24 g Mg
28g -------------------------xg
x=28.24:84=8 g Mg