Răspuns:
a)
CO2
RAPORT ATOMIC =C:O=1:2
RAPORT DE MASA=C:O=12:32=3:8
COMPOZITIE PROCENTUALA
MCO2=AC+2×AO=12+2×16=44g/mol
28gCO2.......12gC.......44gO
100gCO2......xgC.........ygO
x=100×12/44=calculează
y=100×16/44=calculează
b) Ca(OH)2
RAPORT ATOMIC =Ca:O:H=1:2:2
RAPORT DE MASA=Ca:O:H=40:32:2=20:16:1
COMPOZITIE PROCENTUALA
MCa(OH)2=40+2×16+2×1=74g/mol
74gCa(OH)2.............40gCa.................32gO.......2gH
100gCa(OH)2..........xgCa......................ygO...........zgH
x=100×40/74=calculeaza
y=100×32/74=calculeaza
z= 100×2/74=calculeaza
c) MgSO4
RAPORT ATOMIC= Mg: S:O=1:1:4
RAPORT DE MASA = Mg:S:O=24:32:64=3:4:8
COMPOZITEI PROCENTUALA
MMgSO4=24+32+4×16=20g/mol
120 gMgSO4............24 g Mg..............32g S.............64 g O
100g.............................xgMg...............................ygS..........zgO
x=100×24/120=calculeaza
y=100×32/120=calculeaza
Z=120×64/120=calculeaza
d) Ca3(PO4)2
RAPORT ATOMIC= Ca: P:O=3:2:8
RAPORT DE MASA = Ca: P:O=120:62:128=60:31:64
COMPOZITIE PROCENTUALA
MCa3(PO4)2=3×40+2×31+8×16=310g/mol
310g Ca3(PO4)2...................120gCa..............62gP..................128gO
100gCa3(PO4)2.....................xgCa...................ygP....................zgO
x=100×120/310=cacluleaza
y=100×62/310=calculeaza
z=100×128/310=calculeaza
Explicație:
