Răspuns:
1. S+O2=> SO2
2Al+3S=> A2S3
Fe+ S=> FeS
2Fe+ Cl2=> 2FeCl3
SO3+ H2O => H2SO4
MgO+ H2O => Mg(OH)2
2.
MCa=40g/mol
MCaO=40+16=56g/mol
m=6×40=240g
2×40g 2×56g
2Ca + O2=> 2CaO
240g xg
x=240×2×56/2×40=calculează
3.
MCl2=2×35,5=71g/mol
MAlCl3 =27+3×35,5=133,5g/mol
m=7×71=497g Cl2
3×35,5g 2×133,5g
2Al + 3Cl2 =>2 AlCl3
497g yg
y=497×2×133,5/3×35,5=calculează
