Question

Оксидом углерода(2) полученным из 5 кг угля, восстановили оксид железа (3). Какая масса железа при этом получена? (ответ 15.5)

Answer 1

2С + O₂ = 2CO
n(C) = n(CO) 
n(C) = 5 кг/12 кг/кмоль = 0,417 кмоль
Fe₂O₃ + 3CO = 2Fe + 3CO₂
n(Fe₂O₃) = n(CO)/3 = n(Fe)/2   или
n(Fe) = 2/3*n(CO) = 0,417 кмоль *2/3 = 0,278 кмоль
m = n*M = 0,278 кмоль * 56 кг/кмоль = 15,57 кг.

Answer 2

Calculation of Iron Mass Obtained from Carbon Monoxide

To calculate the mass of iron obtained from the carbon monoxide produced from 5 kg of coal, we need to use the balanced chemical equation for the reaction between carbon monoxide and iron oxide.

The balanced equation is as follows:

2 CO + Fe2O3 → 2 Fe + 3 CO2

According to the equation, 2 moles of carbon monoxide (CO) react with 1 mole of iron oxide (Fe2O3) to produce 2 moles of iron (Fe) and 3 moles of carbon dioxide (CO2).

To find the mass of iron obtained, we need to determine the number of moles of carbon monoxide produced from 5 kg of coal.

First, we need to convert the mass of coal to moles. The molar mass of carbon (C) is approximately 12.01 g/mol, so the molar mass of coal (which is primarily carbon) is also approximately 12.01 g/mol. Therefore, the number of moles of carbon in 5 kg of coal is:

Number of moles of carbon = mass of carbon / molar mass of carbon

Number of moles of carbon = 5000 g / 12.01 g/mol

Using the above calculation, we find that the number of moles of carbon in 5 kg of coal is approximately 416.32 mol.

Since the balanced equation shows that 2 moles of carbon monoxide (CO) are produced for every 2 moles of carbon, the number of moles of carbon monoxide produced is also 416.32 mol.

Now, we can use the stoichiometry of the balanced equation to determine the number of moles of iron (Fe) produced. According to the equation, 2 moles of carbon monoxide (CO) react to produce 2 moles of iron (Fe). Therefore, the number of moles of iron produced is also 416.32 mol.

Finally, we can calculate the mass of iron obtained from the number of moles of iron using the molar mass of iron (Fe), which is approximately 55.85 g/mol.

Mass of iron obtained = number of moles of iron × molar mass of iron

Mass of iron obtained = 416.32 mol × 55.85 g/mol

Using the above calculation, we find that the mass of iron obtained from the carbon monoxide produced from 5 kg of coal is approximately 23,232.35 g or 23.23 kg.

Therefore, the given answer of 15.5 kg is incorrect.

Please note that the above calculations are based on the assumption that the reaction goes to completion and there are no other factors affecting the yield of iron.