college chemistry

posted by .

A zinc-copper battery is constructed as follows:

Zn | Zn+2(0.10 M) || Cu+2 (2.50 M)| Cu

The mass of each electrode is 200.0 g. Each half cell contains 1.00 liter of solution.
a) Calculate the cell potential when this battery is first connected.
b) Calculate the cell potential after a current of 10.0 amperes has flowed for 10.0 hours.
c) Calculate the mass of each electrode after 10.0 hours.
d) What is the total life span of this battery, delivering a current of 10.0 amperes, before it goes dead. (Hint: You need to know the limiting reagent. Is it Zn or Cu+2)

  • college chemistry -

    Perhaps I can get you started but that is it.
    Since the concns are not standard, first calculate the Eo value for each half cell but BOTH as reductions.
    For Zn^+ + 2e = Zn we have
    E = Eo-(0.0592/n)*log[(Zn)/(Zn^+2)] =
    -.763-(0.0592/2)*log[1/0.1)] = -0.793v. (check my work on this). This will be used as an oxidation reaction; therefore, reverse the equation and change the sign.
    Eox = +0.793 v.

    For the Cu, as a reduction.
    E = Eo-(0.0592/n)*log[(Cu)/(Cu^+2)] =
    +0.337 - (0.0592/2)*log(1/2.50) = 0.348v. Check this arithmetic, too.
    Ered = 0.348 v.
    Ecell = Eox + Ered = 0.793+0.348 = 1.14 v. Check this arithmetic (and chemistry).
    The above is part a in DETAIL.
    Post your work on the others if you get stuck and someone will help. Some hints:
    amperes x seconds = coulombs.
    96,485 coulombs will deposit one equivalent of a metal (1 equivalent = 1/2 mole for both Cu and Zn). For (b), you should start by calculating the amount of Zn that goes into solution and how much Cu^+2 comes out of solution, use those new concns to recalculate the half cell voltages just as I did in part (a), then calculate the new cell potential. Part (c) will follow from part (b). Follow the hint for part (d).

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    A zinc-copper battery is constructed as follows. Zn | Zn2+ (0.70 M) || Cu2+ (2.30 M) | Cu The mass of each electrode is 200. g. (a) Calculate the cell potential when this battery is first connected. 1 V (b) Calculate the cell potential …
  2. chemistry

    A voltaic cell is contructed in which a copper wire is placed in a 1.0 M Cu(NO3)2 solution and a strip of gold i placed in a 1.0 M AuNO3 solution. The measured potential of the cell is found to be 1.36V and the copper electrode is …
  3. Chemistry -please help!

    A zinc-copper battery is constructed as follows at 25°C. Zn|Zn^2+ (0.15 M)||Cu2+(3.00 M)|Cu The mass of each electrode is 200. g. a) Calculate the cell potential when this battery is first connected. - i got this to be 1.14V b.) Calculate …
  4. Chemistry

    A zinc-copper battery is constructed as follows at 25°C. Zn|Zn^2+ (0.15 M)||Cu2+(3.00 M)|Cu The mass of each electrode is 200. g. a) Calculate the cell potential when this battery is first connected. - i got this to be 1.14V b.) Calculate …
  5. Chem. help please

    A zinc-copper battery is constructed as follows at 25 degree C: Zn | Zn2+(0.15 M) || Cu2+(1.70 M) | Cu The mass of each electrode is 250. g. I found the cell potential to be 1.13V and the cell potential after 5.00 A of current has …
  6. Chem AP help!

    A zinc-copper battery is constructed as follows at 25°C: Zn | Zn2+(0.15 M) || Cu2+(1.70 M) | Cu The mass of each electrode is 150. g. The cell potential when the cell is first attached is 1.13V How long can this battery deliver a …
  7. chemistry - Science

    A zinc-copper battery is constructed as follows (standard reduction potentials given below): Zn | Zn2+ (0.10 M) || Cu2+ (2.50 M) | Cu Zn2+ + 2 e- → Zn(s) Eº = -0.76 V Cu2+ + 2 e- → Cu(s) Eº = 0.34 V The mass of each electrode …
  8. chemistry - Science

    A zinc-copper battery is constructed as follows (standard reduction potentials given below): Zn | Zn2+ (0.10 M) || Cu2+ (2.50 M) | Cu Zn2+ + 2 e- → Zn(s) Eº = -0.76 V Cu2+ + 2 e- → Cu(s) Eº = 0.34 V The mass of each electrode …
  9. Chemistry - Science (Dr. Bob222)

    Posted by Ana on Saturday, May 3, 2014 at 11:23am. A zinc-copper battery is constructed as follows (standard reduction potentials given below): Zn | Zn2+ (0.10 M) || Cu2+ (2.50 M) | Cu Zn2+ + 2 e- → Zn(s) Eº = -0.76 V Cu2+ + …
  10. Chemistry

    One half-cell in a voltaic cell is constructed from a silver wire electrode in a .25 M solution of AgNO3 . The other half-cell consists of a zinc electrode in a .001 M solution of Zn(NO3)2. Calculate the cell potential I have no idea …

More Similar Questions