Balance the following redox reactions by ion- electron method:
`Cr_2O_7^(2-) (aq) + SO_2 (g) rarr Cr^(3+) (aq) + SO_4^(2-) (aq)` (in acidic solution)

Balance the following redox reactions by ion- electron method: MnO_4^(-) (aq) + SO_2 (g) rarr Mn^(2+) (aq) + HSO_4^(-) (in acidic solution)

Balance the following redox reactions by ion- electron method: H_2O_2 (aq) + Fe^(2+) (aq) rarr Fe^(3+) (aq) + H_2O (l) (in acidic solution)

Balance the following redox reactions by ion- electron method: MnO_4^(-) (aq) + I^(-) (aq) rarr MnO_2 (s) + I_2 (s) (in basic medium)

Balanced the following reactions by oxidation number method Cr_2O_7^(2Theta) (aq) + SO_3 ^(2Theta) (aq) rarr Cr^(3Theta) (aq) + SO_4^(2Theta) (aq) (acidic)

Balanced the following reactions by oxidation number method H_2SO_4 (aq) + C(s) rarr CO_2 (g) + SO_2 (g) + H_2O(l) (acidic)

Balance the following redox equation by half reaction method Bi (OH)_3 (s) + SnO_2^(2Theta) (aq) rarr SnO_3^(2Theta) (aq) + Bi (s) (basic)

Balanced the following reactions by oxidation number method MnO_4^Theta (aq) + Br (aq) rarr MnO_2 (s) + BrO_3^(Theta (aq) (basic)

Balanced the following reactions by oxidation number method Bi (OH)_3 (g) + Sn(OH)_3^ Theta (aq) rarr Bi (s) + Sn (OH)_6^(2Theta) (aq) (basic)

Justify the following reactions are redox rections : 4NH_3(g) + 5O_2(g) rarr 4NO(g) + 6H_2O (g)