Question

balance the chemical equation​

Answer 1

1) NO3- + Bi (s) -> Bi3+ + NO2 (g)

Separate half reactions:

NO3- -> NO2 (g)

Bi (s) -> Bi3+

Add H2O to balance oxygen:

NO3 -> NO2 (g) + H2O (l)

Balance hydrogen by adding H+

NO3- + 2H+ (aq) -> NO2 (g) + H2O (l)

Balance charges with e-:

NO3- + 2H+ (aq) + 1e- -> NO2 (g) + H2O (l)

Bi (s) -> Bi3+ + 3e-

Scale reactions so electrons are equal (multiply by 3)

3NO3 - + 6H+ (aq) + 3e- -> 3NO2 (g) + 3H2O (l)

Bi (s) -> Bi3+ + 3e-

Add reactions together and cancel:

3NO3 - + 6H+ (aq) + 3e- + Bi (s) -> 3NO2 (g) + 3H2O (l) + Bi3+ + 3e-

3NO3 - + 6H+ (aq) + Bi (s) -> 3NO2 (g) + 3H2O (l) + Bi3+