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Homework Help: CHEM: Calculate the volume of water expected if the yield of ester were 100%.

  1. Jan 17, 2010 #1
    1. The problem statement, all variables and given/known data

    Calculate the volume of water expected if the yield of ester were 100%.
    19.0mL of n-propanol (0.25 Mol)
    18.5mL(0.25 Mol) propanoic acid.
    5 drops concentrated sulfuric acid


    2. Relevant equations



    3. The attempt at a solution
    C3H7OH + C3H5COOH ---> C6H12O2 + H2O ( not sure this is right)
     
  2. jcsd
  3. Jan 17, 2010 #2

    Borek

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    Reaction is wrong - how many carbons in propanoic acid?

    However, this is a very simple case of 1:1:1:1 reaction - how many moles of products do you expect?
     
    Last edited by a moderator: Aug 13, 2013
  4. Jan 17, 2010 #3
    theres 4, which now makes me confused because the experiment was suppossed to create n-propyl Propanoate. Whiich i thought was CH3CH2C(O)OC3H7 or C6H12O2???

    Also wouldnt you just expect there to be One mole of n-propyl Propanoate and one Mole of H20? How do you find the expected volume of water from that?

    So balance equation = 10C3H7OH + 6C3H5COOH = 9C6H12O2 + 4H2O???


    ** Our lab manual says C3H5COOH is propanoic acid**

    So im assuming thats a typo and should be C3H6O2 Which then made my orignal equation correct

    C3H7OH + C3H6O2---> C6H12O2 + H2O
     
    Last edited: Jan 17, 2010
  5. Jan 17, 2010 #4

    Borek

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    Your manual is wrong, this is a classic mistake.

    What is water density?
     
    Last edited by a moderator: Aug 13, 2013
  6. Jan 17, 2010 #5
    if i recall density of water is 1g/ml.

    So to find Volume you use D=m/v But what is the mass in this case?


     
    Last edited by a moderator: Aug 13, 2013
  7. Jan 17, 2010 #6

    Borek

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    How many moles? Molar mass?
     
    Last edited by a moderator: Aug 13, 2013
  8. Jan 17, 2010 #7
    1 mol?? or is it 0.25 Our lab manual is very unorganized.. molar mass is 18.0153 g/mol.
     
  9. Jan 17, 2010 #8

    Borek

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    If they react 1->1, and you start with 0.25 mole, how many moles of water are produced? How many grams it is?
     
    Last edited by a moderator: Aug 13, 2013
  10. Jan 17, 2010 #9
    mass = n x MM
    Therefore 0.25 moles X 18.015 molar mass =4.50 g

    then Volume = mass/density

    Volume= 4.50g/ 1.0g cm^3
    Volume= 4.50 mL??
     
  11. Jan 18, 2010 #10

    Borek

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    Wasn't that hard :wink:
     
    Last edited by a moderator: Aug 13, 2013
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