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Long-winded finding of Limiting Reagent

  1. Dec 2, 2004 #1

    Balanced Equation

    CH3C(O)-O-C(O)CH3(l) + C7H6O3(l) ---> C2H4O3 + C6H4(OCOCH3)CO2H

    Trying to find limiting reagent here...

    mWt CH3C(O)-)-C(O)CH3(l) = 102.09 g/mol
    5.4/102.09 = 0.53 mol

    mwt C7H6O3(l)= 138.12 g/mol
    1.5g/138.12 = 0.011 mol

    I have the actual percent yield (as per experiment) at 7.43% but I also need the theoretical yield.
  2. jcsd
  3. Dec 6, 2004 #2


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    Science Advisor
    Gold Member

    Practical yields are calculated on theoretical yields, which is assumed 100%. In your example, salicylic acid is the limiting reagent, since it is only present in 11 millimoles compared with 530 millimoles of acetic anhydride.

    [tex]C_7H_6O_3[/tex] gives [tex]C_6H_4(OCOCH_3)CO_2H[/tex], so 102.09 g of the first compound will give [tex]C_9H_8O_4=180.16 g/mol[/tex]. If you isolated the product with about 7.5% yield, then your final product weighs about 0.145 grams, right?
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