Respuesta :
Fe3O4 (s) + 2 C (s) -> 3 Fe (s) + 2 CO2 (s)
from equation 1 mol 2 mol
Given 35.0 g Fe3O4 and 4.0 g C , we need to convert them into moles.
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35.0 g Fe3O4
M(Fe3O4) = 55.8 g/mol
35.0 g Fe3O4 * 1 mol Fe2O3/55.8 g Fe2O3 = 0.6272 mol Fe2O3
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4.0 g C
M(C) = 12 g/mol
4.0 g C* 1mol C/12 g C = 0.3333 mol C
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Fe3O4 (s) + 2 C (s) -> 3 Fe (s) + 2 CO2 (s)
from equation 1 mol 2 mol
given 0.6272 mol 0.3333 mol
We can see that Fe3O4 is an excess reactant,
so to find the amount of Fe we are going to use carbon.
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Fe3O4 (s) + 2 C (s) -> 3 Fe (s) + 2 CO2 (s)
from equation 2 mol 3 mol
given 0.3333 mol x mol
x=0.3333*3/2= 0.500 mol Fe is theoretical yield
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Actual yield Fe is 15 g.
15 g Fe* 1 mol/55.8 g = 0.2688 mol Fe is actual yield
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% yield = (actual yield/ theoretical yield)* 100% = (0.2688/0.500)*100%=53.8%
% yield = 53.8%