4 Fe(s) + 3 O2(g) 2 Fe2O3(s) ΔH = -1652 kJ
How much heat is released when 3.82 mol iron is reacted with excess O2?
1652 kJ x (3.82 moles/4 moles) = ??
1652 x (3.82 moles/4 moles) = 1577.66
To determine the amount of heat released when 3.82 mol of iron (Fe) is reacted with excess oxygen (O2), we can use the stoichiometry of the balanced equation and the given enthalpy change (ΔH) value.
The coefficient ratio between Fe and Fe2O3 in the balanced equation is 4:2, or 2:1. This means that for every 2 moles of Fe2O3 formed, 4 moles of Fe are consumed.
Given that 4 Fe(s) + 3 O2(g) -> 2 Fe2O3(s) has a ΔH = -1652 kJ, we can set up a proportion to find the amount of heat released when 3.82 moles of Fe are reacted:
(3.82 mol Fe) / (4 mol Fe) = (x kJ) / (-1652 kJ)
Simplifying the equation, we get:
x = (3.82 mol Fe / 4 mol Fe) * (-1652 kJ)
x ≈ -1567.5 kJ
Therefore, approximately -1567.5 kJ of heat is released when 3.82 mol of iron is reacted with excess O2.
To calculate the amount of heat released when a certain amount of substance is reacted, we need to use the stoichiometry of the balanced equation and the given ΔH value.
In this case, the balanced equation is:
4 Fe(s) + 3 O2(g) → 2 Fe2O3(s)
The stoichiometric ratio between Fe and Fe2O3 is 4:2, which means that for every 4 moles of Fe reacted, we produce 2 moles of Fe2O3.
First, we need to calculate the number of moles of Fe2O3 produced when 3.82 mol of Fe is reacted. We can use the stoichiometry to do this:
(3.82 mol Fe) × (2 mol Fe2O3 / 4 mol Fe) = 1.91 mol Fe2O3
Now, we can use the ΔH value to calculate the heat released. The ΔH value tells us the heat released for the reaction of 4 moles of Fe, so we need to calculate the heat released for 1.91 moles of Fe2O3:
ΔH = -1652 kJ
Heat released for 1 mole of Fe2O3 = -1652 kJ / 4 mol Fe2O3
Heat released for 1.91 moles of Fe2O3 = (-1652 kJ / 4 mol Fe2O3) × 1.91 mol Fe2O3
Finally, we can multiply the result by 1000 to convert kJ to J:
Heat released = [(-1652 kJ / 4 mol Fe2O3) × 1.91 mol Fe2O3] × 1000 J/kJ
By performing the necessary calculations, you will find the amount of heat released when 3.82 mol of iron is reacted with excess O2.