1) 2Cr+6HCL=2CrCl₃+3H₂
2) 2CrCl₃+3NaOH=Cr(OH)₃ + 3NaCl
3) 2Cr(OH)₃ Cr₂O₃ + 3H₂O
4) Cr₂O₃ + 2Al = Al2O3 + 2Cr
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