Al2O3
raport atomic=r.a.=2 Al :3 O=2:3
raport de masa =r.m.=2AAl:3AO=2.27:3.16=54:48=9:8
( se simplifica cu 6 )
compozitie proc. prin masa moleculara
MA2O3=2.27+3.16=102
102 g Al2O3----54 g Al-------48gO
100g-------------------x---------------y
x=100.54:102=52,94 la suta Al
y=100.48:102=47,05 la suta O
Ca(OH)2
r.a.=1Ca :2O:2H=1:2:2
r.m.=ACa :2AO:2AH=40:2.16:2=40:32:2=20:16:1
comp. proc.prin masa molec.
M=40+2.16+2=74
74 g Ca(OH)2------40 gCa-------32 gO-------2 g O
100 g-------------------------x---------y------------z
x=100.40:74=54,05 la suta Ca
y=100.32:74=43,24 la suta O
Z=100.2:74=2,70 la suta H
(NH4)2 CO3
r.a.=2N:8H:1C:3O=2:8:1:3
r.m.=2AN:8AH:AC:3AO=2.14:8:12:3.16=28:8:12:48=7:2:3:12
( se simpl. cu 4)
Comp. proc.
M=2.14+8+12+3.16=28+20+48=96
96 g( NH4)2CO3---------28 gN-------8 gH-------12 gC--------48 gO
100 g----------------------x-------------------y-----------z--------------a
x=100.28:96=29,16 la suta N
Y=100.8:96=8,33 la suta H
Z=100.12:96=12,5 la suta C
a=100.48:96=50 la suta O
