Suppose the galvanic cell sketched below is powered by the following reaction: 3

Question

Suppose the galvanic cell sketched below is powered by the following reaction: 3Zn(s) + 3Fe(NO_3)_3 (aq) 3Zn(NO_3)_2 (aq) + 2Fe(s) 3Zn(s) + 2 Fe(NO_3)_3 (aq) rightarrow 3 Zn(NO_3)_2 (aq) + 2 Fe(s) Write a balanced equation for the half-reaction that happens at the cathode of this cell. Write a balanced equation for the half-reaction that happens at the anode of this cell. Of what substance is E1 made? Of what substance is E2 made? What are the chemical species in solution S1? What are the chemical species in solution S2?

Explanation / Answer

Q8.

E1 is lossing electrons, so it must be the anode

E2 is gaining electrons, so it is the cathode

the reaction isfavoured as followS:

Zn2+ + 2 e Zn(s) 0.7618

Fe3+ + 3 e Fe(s) 0.04

then, clearly, Zinc will oxidize, it will be the anode, Iron is the cathode

reaciton:

2Fe3+ + 6e 2Fe(s) 0.04 cathode

3Zn(s)   3Zn2+ + 6e 0.7618 anode

E° = Ered + Eox = -0.04 + 0.7618 = 0.7218V

the reaction balanced:

3Zn(s) +2Fe3+ + 6e 2Fe(s) + 3Zn2+ + 6e

cancel common terms

3Zn(s) +2Fe3+ 2Fe(s) + 3Zn2+

nte that NO3- is spectator ion, so simply add it:

3Zn(s) +2Fe(NO3)3 2Fe(s) + 3Zn(NO3)2 overall reaction

E1 --> is makeing Zn2+

E2 --> is making Fe(s)

S1 --> this must be Fe3+

S2 --> this must be Zn2+

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.