1)Fe+2HCl=FeCl2+H2
2)FeCl2=Fe+Cl2
3)Fe+H2SO4=FeSO4+H2
4)FeSO4+2NaOH=Fe(OH)2+Na2SO4
M(H2O) = m(p-pa)*(100-W)/100 = 200*40/100 = 80г
NaF=Na+F-, PdCl4= CL-Pd+4, MgS=Mg+2 S-2, Mn2O7=O-2Mn+7, NaNO2=Na+N+3O-2,
K2SO4=K+S+6O-2, Ba3(PO4)2=Ba+2P+3O-2
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