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!

33.39 mL of the I2 solution from above is required to titrate a sample

  1. Oct 19, 2013 #1
    1. The problem statement, all variables and given/known data
    33.39 mL of the I2 solution from above is required to titrate a sample containing As2O3. Calculate the mass of As2O3 (197.8 g/mol) in the sample.

    As2O3 + 5(H2O) + 2I2 → 2(H3AsO4) + 4HI


    2. Relevant equations


    3. The attempt at a solution
    MolarMass_I2=254 g/mol
    MolarMass_As2O3=197.8 g/mol
    1 mol As2O3:2mol I2

    I know I would have to get the mol of both I2 and As2O3 somehow in order to plug them into that relationship above.

    I think Molarity may possibly be involved.

    The problem is that while I know that there is 0.03339 L of I2, I don't know the concentration of I2 so i don't know how I can arrive at the number of mol of I2.
    1. The problem statement, all variables and given/known data
    2rr32iv.gif
    How many sigma bonds? pi bonds?

    3. The attempt at a solution
    There are 6 sigma bonds since there are a total 6 of bonds between 6 atoms since all atoms have electrons in the s orbital.
    There are 4 pi bonds between N and C, C and C, C and C, C and C. This is because each atom has electrons in orbital 2p.
     
    Last edited: Oct 19, 2013
  2. jcsd
  3. Oct 20, 2013 #2

    Borek

    User Avatar

    Staff: Mentor

    No way to solve the first problem without knowing concentration of iodine - but the problem states "solution from above", so most likely there were some information provided earlier.

    Check what are pi bonds.
     
  4. Oct 20, 2013 #3
    Well... I didn't see the "solution above part". The solution of I2 has a molarity of 1.29 M. Using that, I found that the mass of As2O3 is 4.26g.

    Also, pi bonds are the hybrid orbitals formed from the overlapping of 2 p orbitals.
     
  5. Oct 20, 2013 #4

    Borek

    User Avatar

    Staff: Mentor

    Which bonds are created first - sigma, or pi? Is it possible to have a pi bond without sigma?
     
  6. Oct 20, 2013 #5
    I believe sigma bonds are created first. All ground state atoms will have s orbitals so for ground state atoms, there must always be sigma bonds right? If excited, then pi bonds can exist without sigma bonds.
     
  7. Oct 20, 2013 #6

    Borek

    User Avatar

    Staff: Mentor

    Good. Now, wherever there are two atoms bonded, first bond is sigma, rest - if they exist - are pi. How many sigma bonds? How many pi bonds?
     
  8. Oct 20, 2013 #7
    Oh ok. i get it now. 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: 33.39 mL of the I2 solution from above is required to titrate a sample
  1. % of titrated sample (Replies: 6)

  2. Ppm of iron from mL ? (Replies: 3)

Loading...