K2Cr2O7 + H2SO4 + KI = Cr2(SO4)3 + I2 + K2SO4 + H2O
Cr2O7(2-) + 14H(+) + 6e = 2Cr(3+) + 7H2O
2I(-) -2e = I2 } x3
K2Cr2O7 + 7H2SO4 + 6KI = Cr2(SO4)3 + 3I2 + 4K2SO4 + H2O
K2Cr2O7 + H2SO4 + KI = Cr2(SO4)3 + I2 + K2SO4 + H2O
Cr2O7(2-) + 14H(+) + 6e = 2Cr(3+) + 7H2O
2I(-) -2e = I2 } x3
K2Cr2O7 + 7H2SO4 + 6KI = Cr2(SO4)3 + 3I2 + 4K2SO4 + H2O