Cr+2HCl=CrCl2+H2O
2CrCl2+Cl2=2CrCl3
CrCl3+3NaOH=Cr(OH)3+3NaCl
Cr(OH)3+3KOH=K3[Cr(OH)6]
K3[Cr(OH)6]+3H2O2=2K2Cr2O4+2KOH+8H2O
2K2Cr2O4+2HCl=K2Cr2O7+2KCl+H2O
6FeSO4+K2Cr2O7+7H2SO4=3Fe2(SO4)3=Cr2(SO4)3+K2SO4+7H2O
Cr2(SO4)3+6NaOH=2Cr(OH)3+3Na2SO4
2Cr(OH)3=Cr2O3+3H2O
Cr2O3+3CO=2Cr+3CO2