Răspuns:
2.a. CaBr₂
b. SiO₂
c. Na₂CO₃
d. Al₂(SO₄)₃
3.a. MFeF3=AFe+3AF=56+3•19=56+57=113g/mol
b. MZn(OH)2=AZn+2AO+2AH=65+2•16+2•1=65+32+2=99g/mol
4. a. mPH3=?
nPH3=7 moli
m=n•M
MPH3=AP+3AH=31+3•1=34g/mol
m=7mol•34g/mol=238g
5. FeS+2HCl=FeCl2+H2S
2KOH+H2SO4=K2SO4+2H2O