(23.Chemistry - Science (Dr. Bob222)

posted by .

An electrochemical battery made from Sn and Cu electrodes under standard conditions shows an
initial voltage of V= 1.1 V. If the concentration of both Cu2+ and Sn2+ solutions is increased to 2 M from
1 M, the observed voltage will: (Hint: use the Nernst equation)
A. increase
B. increase if Sn is oxidized
C. increase if Cu is oxidized
D. remain the same
E. C. decrease

  • (23.Chemistry - Science (Dr. Bob222) -

    The correct answer is D.
    But my question is how is it possible to have an initial voltage of 1.1V for the cell is with concentration of 1M, if E standard for the cell is 0.48.
    I am sure I am missing something here.

  • (23.Chemistry - Science (Dr. Bob222) -

    I'm not Dr. Bob222, but I play on this site every now in then. I think you are confused because of the wording of the question; you are not calculating Eo based on the information that a chart in your book gives you, but they are just giving you Eo and asking you based on the concepts, what will happen. You are correct: Eo should be equal to 0.48, based on information from your book, but they are giving you a number and asking you how it will change. You can use the Eo value that you calculated or you can use the value that they give you; either value will return the same answer. The Nernst equation is as followed:

    E = Eo −(0.0592Vnl)ogQ

    As, you can see if you substitute 1M or 2M values for Cu2+ or Sn2+ into Q, you will just get Eo, since log of 1 is equal to 0. And 0 times any number equals 0. So, E will be equal to Eo and the value will not change, or better yet the value will remain the same. D is the best answer choice.

    E = Eo

  • (23.Chemistry - Science (Dr. Bob222) -

    Thank you Devron for explication.

  • (23.Chemistry - Science (Dr. Bob222) -

    This Q. seemed too easy to me, and I though it must be a trick question or something, nonetheless thank you for explaining.

  • (23.Chemistry - Science (Dr. Bob222) -

    Devron is right but I want to add a point or two.
    First, Ana is right. It PROBABLY isn't possible unless the reaction is carried out in under other than standard conditions; i.e., basic solution, complexing materials added to the basic mix, etc. Devron is right that none of that matters.
    What does matter?
    That log term matters. log (1/1) = 0; log (2/2) = 0 and in fact anything they do to the numerator doesn't matter as long as the same is done to the denominator because log x/x = 0

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. ap chemistry

    I have a lot of questions actually. it's electrochemistry (which is obviously a bunch of fun) 2 electrodes Cr(s)/Cr3+ and Sn(s)/Sn2+ are combined to afford a spontaneous electrochemical reaction. the standard reduction potention in …
  2. Chemistry

    A battery is constructed based on the oxidation of magnesium and the reduction of Cu^2+. The initial concentrations of Mg^2+ and Cu^2+ are 1.2*10^-4M and 1.5M, respectively, in 1.0-L half-cells. The initial voltage of the battery is …
  3. chemistry

    I need assistance with this question please. "The equation of the line for a graph of voltage (Ecell) versus log[Cu2+] was y= -0.0166x - 0.0082. The voltage of a solution with an unknown [Cu2+] was measured against the same reference …
  4. Chemistry

    the equation of the line for a graph of voltage versus log[Cu2+] was y= - 0.0179x - 0.0015. The voltage of a solution with an unknown [Cu2+] was measured against the same reference cell, under the same conditions; the voltage was found …
  5. Chemistry

    The equation of the line for a graph of voltage versus log[Cu2+] was y= - 0.0179x - 0.0015. The voltage of a solution with an unknown [Cu2+] was measured against the same reference cell, under the same conditions; the voltage was found …
  6. CHEMISTRY

    The half-cell, Tl | Tl+(1 mol L-1), is connected to a Pt | H+ | H2(1 atm) half-cell in which the concentration of H+ is unknown. The measured cell voltage is 0.0841 V and the Pt | H2 | H+ half-cell is the cathode. Standard reduction …
  7. CHEMISTRY

    The half-cell, Tl | Tl+(1 mol L-1), is connected to a Pt | H+ | H2(1 atm) half-cell in which the concentration of H+ is unknown. The measured cell voltage is 0.0841 V and the Pt | H2 | H+ half-cell is the cathode. Standard reduction …
  8. Chemistry- Dr.Bob222

    Using the Nernst equation, determine the diluted concentration for both cells. Show your work. Given that [Cu2+] and [Zn2+] are both 2M. Note: I know that the nernst equation is E= E*cell=(-0.0592 V/n)log Q where Q in this case are …
  9. Chemistry- Dr.Bob222

    Using the Nernst equation, determine the diluted concentration for both cells. Show your work. Given that [Cu2+] and [Zn2+] are both 2M. Note: I know that the nernst equation is E= E*cell=(-0.0592 V/n)log Q where Q in this case are …
  10. Chemistry- Dr.Bob222

    Using the Nernst equation, determine the diluted concentration for both cells. Show your work. Sn| Sn2+(diluted)||Cu2+|Cu Zn| Zn2+ ||Sn2+(diluted)|Sn

More Similar Questions