Question

If 15.6 grams of iron (III) oxide reacts with 12.8 grams of carbon monoxide to produce 9.58 g of pure iron, what are the theoretical yield and percent yield of this reaction? Be sure to show the work that you did to solve this problem.

unbalanced equation: Fe2O3 + CO “yields”/ Fe + CO2

Answer 1

balanced it would be Fe2O3 + 3CO ->2Fe+ 3CO2

Answer 2

Good job balancing. The first step is to find the limiting reactant, so that we can find the theoretical yield.

Answer 3

Any ideas on how to do that?

Answer 4

i believe it would be iron

Answer 5

Iron can't be the limiting reactant. Iron is a product.

Answer 6

it has to be because there is an excess of CO

Answer 7

Do you mean that iron(III) oxide is limiting?

Answer 8

And how do you know that there is an excess of CO?

Answer 9

yes i mean iron(III) oxide, and because there is more iron than there is carbon monoxide

Answer 10

Limiting doesn't mean that there is less of a reactant. It means that reactant produces less product.

Answer 11

Sometimes you may have a limiting reactant that you start with more of.

Answer 12

What I would do to find which reactant is limiting is to start with the mass of each and use conversions to find how much of one of the products I can make.

Answer 13

Can you start with the mass of iron(III) oxide and convert to the mass of iron you would produce?

Answer 14

Hint* You will need the molar mass and the molar ratio.

Answer 15

i got
156Fe3*(1molFe2O3/159.69) *(3molCo/1molFe203*28Co)
which would equal 8.2CO

Answer 16

Ok, that works. So, if you use up all of your iron oxide, you only need 8.2 g of CO to react. Do you have enough with what you are given?

Answer 17

yes

Answer 18

So, you were right about which on is limiting. I just wanted to make sure you knew why. :)

Answer 19

c: okay and then i got
(128CO*1molCO/28) * (1molFe2O3/3molCO) *159.68FE2O3/1mol) 24.33FE2O3

Answer 20

Right, you need more than you have for iron oxide. So it is limiting.

Answer 21

So now, we can use the limiting reactant to calculate the mass of Fe produced. That would be the theoretical yield.

Answer 22

10.91

Answer 23

There you go. :)

Answer 24

9.58g is actual yield.

Answer 25

Can you now calculate the percent yield?

Answer 26

(9.58/10.91)*100%=87.8%

Answer 27

Perfect! :)

Answer 28

yay thank you c:

Answer 29

No worries