Question

K2Cr2O7+H2SO4+C2H5OH
Составить реакцию и уровнять методом полуреакций

Answer 1

2K2Cr2O7 + 8H2SO4 + 3C2H5OH = 2K2SO4 + 2Cr2(SO4)3 + 3H3C-COOH + 11H2O, баланс:

(Cr2O7)2- +6e- + 14H+ = 2Cr3+ + 7H2O      | 6 | 12 | 2 |

C2H5OH -4e- + H2O = H3CCOOH + 4H+     | 4 |     | 3 |;

2(Cr2O7)2- + 3C2H5OH + 16H+ = 4Cr3+ + 3H3CCOOH + 11H2O.

Answer 2

C2H5OH -2e- = H3CCHO + 2H+ | 2 | | 3 |;

Answer 3

(Cr2O7)2- + 3C2H5OH + 8H+ = 2Cr3+ + 3H3CCHO + 7H2O;