Question

Скільки грам кисню необхідно взяти для спалювання 8 г заліза, що утвооилась залізна ожарена

Answer 1

Тут может быть несколько решений в зависимости от валентности ферума:

1 Вариант

2Fe + O2 = 2FeO

m(Fe) = 8 г

m(O2) - ?

Решение:

1) μ(Fe) = 8г / 56 г/моль = 0.142моль

μ(O2) = 0.142 моль / 2 = 0.71 моль

m(O2) = 0.71 моль * 32 г/моль = 22.72 г

Ответ: 22.72г

2 Вариант

4Fe + 3O2 = 2Fe2O3

m(Fe) = 8г

m(O2) - ?

Решение:

1) μ(Fe) = 8г / 56 г/моль = 0.142моль

μ(O2) = (μ(Fe) / 4 )* 3 = 0.1065 моль

m(O2) = 0.1065 моль * 32 г/моль = 3.408 г

Ответ: 3.408г

Answer 2

Calculating the Amount of Oxygen Needed to Burn Iron

To calculate the amount of oxygen needed to burn 8 grams of iron, we can use the balanced chemical equation for the combustion of iron:

4Fe + 3O2 → 2Fe2O3

This equation shows that 4 moles of iron react with 3 moles of oxygen to produce 2 moles of iron(III) oxide.

Calculating the Moles of Iron

First, we need to convert the mass of iron (8 grams) to moles. The molar mass of iron is approximately 55.85 g/mol.

So, moles of iron = mass of iron / molar mass of iron = 8 g / 55.85 g/mol.

Calculating the Moles of Oxygen

Using the stoichiometry of the balanced chemical equation, we can determine the moles of oxygen needed to react with the moles of iron.

From the balanced equation, we know that 4 moles of iron react with 3 moles of oxygen.

Calculating the Amount of Oxygen Needed

Now, we can calculate the amount of oxygen needed to burn 8 grams of iron using the mole ratio from the balanced chemical equation.

moles of oxygen needed = moles of iron * (3 moles of O2 / 4 moles of Fe).

Final Calculation

After calculating the moles of oxygen needed, we can convert this to grams using the molar mass of oxygen (approximately 16 g/mol).

grams of oxygen needed = moles of oxygen * molar mass of oxygen.

Let's calculate the amount of oxygen needed.