what is the limiting reactant if 0.10 moles Fe and 0.16 moles O2 react according to the reaction 4Fe +3O2 -> 2Fe2O3?
0.1 mol Fe x (2 mol Fe2O3/4 mol Fe) = 0.1 x 1/2 = 0.05 mol Fe2O3 produced if we had 0.1 mol Fe and all the O2 we needed.
0.16 mol O2 x (2 mol Fe2O3/3 mol O2) = 0.16 x 2/3 = 0.107 mol Fe2O3 produced if we had 0.16 mol O2 and all the Fe we needed.
So Fe must be the limiting reagent as that produces the least amount of Fe2O3.
To determine the limiting reactant in a chemical reaction, you need to compare the moles of each reactant to their stoichiometric coefficients in the balanced equation.
In the given reaction: 4Fe + 3O2 -> 2Fe2O3
The stoichiometric coefficients indicate that 4 moles of Fe react with 3 moles of O2 to produce 2 moles of Fe2O3.
Step 1: Calculate the moles of Fe and O2
- Moles of Fe = 0.10 moles
- Moles of O2 = 0.16 moles
Step 2: Use the stoichiometric coefficients to determine the moles needed to react completely.
- For Fe: Using the ratio 4:2, you need (0.10 moles Fe) x (3 moles O2 / 4 moles Fe) = 0.075 moles O2.
- For O2: Using the ratio 3:2, you need (0.16 moles O2) x (4 moles Fe / 3 moles O2) = 0.213 moles Fe.
Step 3: Compare the moles needed to react with the actual moles given for each reactant.
- Fe: Actual moles (0.10 moles) < Moles needed (0.075 moles)
- O2: Actual moles (0.16 moles) > Moles needed (0.213 moles)
Step 4: The reactant that produces fewer moles of the product is the limiting reactant. In this case, Fe is the limiting reactant because it produces fewer moles of Fe2O3 compared to O2.
Therefore, Fe is the limiting reactant in this reaction.