1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Contradicting predictions

  1. Mar 23, 2005 #1
    Ok this is about electrolysis of sodium Sulphate

    I believe the formula is

    Na2SO4 + 2H2O ----> 2NaOH + H2SO4

    During the lab, the indicator at the cathode turned basic and the anode indicated acidic.

    Explaining this using electric potentials:
    Na + e = Na E = -2.71 V
    H2O + e = ½ H2 + OH- E = -0.83 V
    S2O8 + 2e = 2SO4 E = 2.05 V
    ½ O2 + 2H = H2O E = 1.23 V

    water = 1.23 – (-0.83) = 2.06 V
    sodiumSulphate = 2.05 – (-2.71) = 4.76 V

    The battery used were 3V

    I have no idea how this results in the original reaction formula above. Can someone englighten me? :smile:
     
    Last edited: Mar 23, 2005
  2. jcsd
  3. Mar 23, 2005 #2
    ummm i think i solved the problem, but thanks anyway.

    Dunno how to delete the thread :cry:
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook