Question

Use the following pair of half-reactions to design a galvanic cell. Then write in the proper coefficient for each of the species involved in the overall reaction. Water molecules and protons are not shown in the half-reactions, but may need to be added to the overall reaction.

N2 (g)→N2H5+ (aq)

MnO4- (aq)→Mn2+ (aq)

Find coefficients for
MnO4- (aq)
N2 (g)
Mn2+ (aq)
N2H5+ (aq)
H+ (aq)
H2O (l)

Answer 1

The coefficients for the species involved in the overall reaction are as follows:

MnO4- (aq): 1

N2 (g): 1

Mn2+ (aq): 1

N2H5+ (aq): 1

H+ (aq): 13

H2O (l): 4

To design a galvanic cell using the given pair of half-reactions and determine the coefficients for each species involved in the overall reaction, we need to balance the half-reactions and combine them to form the overall reaction.

The half-reactions are as follows:

N2 (g) → N2H5+ (aq)

MnO4- (aq) → Mn2+ (aq)

To balance the half-reaction for the reduction of MnO4- to Mn2+:

MnO4- + 8H+ + 5e- → Mn2+ + 4H2O

To balance the half-reaction for the oxidation of N2 to N2H5+:

N2 + 5H+ + 5e- → N2H5+

Now, we can combine the two balanced half-reactions to form the overall reaction:

N2 + 5H+ + 5e- + MnO4- + 8H+ + 5e- → N2H5+ + Mn2+ + 4H2O

Simplifying the reaction by canceling out common species on both sides:

N2 + MnO4- + 13H+ → N2H5+ + Mn2+ + 4H2O

Finally, let's determine the coefficients for each species involved:

MnO4- (aq): 1

N2 (g): 1

Mn2+ (aq): 1

N2H5+ (aq): 1

H+ (aq): 13

H2O (l): 4