1. Not finding help here? Sign up for a free 30min 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!

Combustion of Toluene with 30% excess air (Himmelblau)

  1. Jul 5, 2017 #1
    1. The problem statement, all variables and given/known data
    Toluene, C7H8, is burned with 30% excess air. A bad burner cause 15% of the carbon to
    form soot (pure C) deposited on the walls of the furnace, what is the Orsat analysis of the
    gases leaving the furnace?


    2. Relevant equations
    C7H8 + 9 O2 => 7 CO2 + 4 H2O
    30% excess of air

    What would be the theoretical toluene on which the excess air is based?

    3. The attempt at a solution
    I get lost with the "A bad burner cause 15% of the carbon to
    form soot (pure C) deposited on the walls of the furnace".
    If it weren't for that, I could solve this problem easily!

    I need help with the 15% carbon to soot.
     
  2. jcsd
  3. Jul 5, 2017 #2

    Borek

    User Avatar

    Staff: Mentor

    Of each mole of carbon present in the toluene, how many moles will reach the apparatus?
     
  4. Jul 5, 2017 #3
    Hi, Borek.

    Ok, supposing there are an initial 100 kg-mol of toluene, C7H8.
    Each mole has 7 moles of carbon, C.
    Then we have 700 kg-mol of C.
    The 15% of that is 105 kg-mol.

    That means that 85% of toluene will react with oxygen.
    Buuuuttt... what happens with the other hydrogen in toluene, C7H8, since Carbon formed soot (pure C), does the hydrogen form H2?

    Is the 30% of excess air based on the 85 kg-mol of toluene that do react with oxygen or the original amount?
    That's my doubt! Thanks for your time.
     
  5. Jul 5, 2017 #4

    Borek

    User Avatar

    Staff: Mentor

    You are over complicating it. You are not told anything about hydrogen so simply assume it is all converted to H2O.

    Excess air doesn't matter - your analysis detects only gaseous combustion products.
     
  6. Jul 5, 2017 #5
    Wow, wow, wow!
    I never thought of that!

    Yeah, obviously, the rest of hydrogen forms water with the oxygen of air.

    I need to do the calculations.

    Thanks!!!!!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Combustion of Toluene with 30% excess air (Himmelblau)
  1. Excess reactant (Replies: 6)

  2. Methane-air combustion (Replies: 10)

  3. Moles of excess (Replies: 6)

  4. Excess reactant (Replies: 6)

Loading...