Question

Сколько энергии выделится при восстановлении алюминием оксида железа (III) массой 32г если тепловой эффект этой реакции равен 853,7 кДж?

Answer 1

Fe₂O₃+2Al=Al₂O₃+2Fe   +853.7кДж
n(Fe₂O₃)=32/160=0.2моль
при n(Fe₂O₃)=1 моль -----853.7кДж
при n(Fe₂O₃)=0.2 моль------Q
Q=0.2*853.7=170.74кДж

Answer 2

Calculation of Energy Released in the Reaction

To calculate the amount of energy released in the reaction of aluminum with iron(III) oxide, we can use the given heat effect of the reaction, which is 853.7 kJ.

The balanced chemical equation for the reaction is:

2 Al + Fe2O3 -> Al2O3 + 2 Fe

From the balanced equation, we can see that 2 moles of aluminum react with 1 mole of iron(III) oxide to produce 1 mole of aluminum oxide and 2 moles of iron.

To find the energy released per mole of the reaction, we divide the given heat effect by the stoichiometric coefficient of the reaction:

Energy released per mole of reaction = 853.7 kJ / 2 = 426.85 kJ

Now, we need to find the number of moles of iron(III) oxide used in the reaction. We are given the mass of iron(III) oxide as 32 g.

To find the number of moles, we can use the molar mass of iron(III) oxide (Fe2O3), which is 159.69 g/mol:

Number of moles of Fe2O3 = Mass / Molar mass = 32 g / 159.69 g/mol ≈ 0.2004 mol

Finally, we can calculate the total energy released in the reaction by multiplying the energy released per mole of reaction by the number of moles of iron(III) oxide:

Total energy released = Energy released per mole of reaction * Number of moles of Fe2O3 = 426.85 kJ/mol * 0.2004 mol ≈ 85.5 kJ

Therefore, approximately 85.5 kJ of energy will be released in the reaction of aluminum with iron(III) oxide with a mass of 32 g.