Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Mechanism for Phosgene Formation

  1. Feb 20, 2015 #1
    The overall reaction for the formation of phosgene from Cl2 and CO is:

    Cl2 + CO --> Cl2CO

    The mechanism is:

    Cl2 + M <--> 2Cl' + M
    Cl' + CO <--> ClCO'
    ClCO' + Cl2 --> Cl2CO + Cl'

    For this mechanism, the sum of the elementary reactions is:

    2Cl2 + CO --> Cl2CO + 2Cl'

    However, doesn't the sum of the elementary reactions need to add up to the overall reaction?
  2. jcsd
  3. Feb 20, 2015 #2

    Quantum Defect

    User Avatar
    Homework Helper
    Gold Member

    Multiply reaction 2 and 3 by 2 and add these together with one and you will be get the net reaction. Remember that in real systems, you will have lots of reactions. Adding all of the possible reactions together doesn't necessarily give you the net reaction. E.g in the system above, you will also have recombination -- the reverse of reaction one. You could also add reaction -1 to what you have to get the net reaction. This does not mean that this is what the atoms are doing.
  4. Feb 20, 2015 #3
    Got it, thank you!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook