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!

Lab doubt

  1. Mar 4, 2009 #1

    z89

    User Avatar

    Actually this is a part of homework. I've found the answer, but I have some problems.

    The lab I did in previous lesson is the preparation of K3Fe(C2O4)3.3H2O from Fe(NH4)2(SO4)2.6H2O

    In the first step, Iron(II) ammonium sulphate was reacted with oxalic acid dihydrate to form Iron(II) oxalate precipitate.

    In the second step, Iron(II) oxalate was oxidized to potassium trioxalatoferrate(III) K3Fe(C2O4)3 by addition of H2O2 and K2C2O4.

    In fact, I found link(s) talking about the lab

    http://www.chem.umass.edu/genchem/chem112/112_Experiment_1.htm

    but I was a bit doubt about the equation mentioned. I observed that there was bubbles formed/gas evolving in step 2. I believed that this is not oxygen, since Fe2+ is oxidized to Fe3+ in this process, H2O2(O: -1 in ON) cannot be oxidized to O2(O: 0) in the same time.
    Therefore, it should be CO2, which was oxidized from oxalate, am I right?

    And then, why the equation did not mention the oxidization of oxalate.... even the release of gas

    of course, this problem didn't affect the calculation process. I am just curious ..
    Thanks.
     
  2. jcsd
  3. Mar 4, 2009 #2

    chemisttree

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    I've known iron salts to catalytically decompose hydrogen peroxide into water and oxygen. Was the peroxide present in excess?
     
  4. Mar 4, 2009 #3

    z89

    User Avatar

    yes, thanks for your reminder:biggrin:

    but, is the reaction between oxalate and H2O2 favourable?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Lab doubt
  1. Osmosis Lab (Replies: 1)

  2. Lab question (Replies: 3)

  3. Buffers Lab (Replies: 1)

  4. Lab report (Replies: 1)

Loading...