# Long-winded finding of Limiting Reagent

1. Dec 2, 2004

### Up_Creek

Ok.

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. Dec 6, 2004

### chem_tr

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.

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

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