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The process of reducing metal oxides

Reducing metal oxides is one method used to produce metals, which requires a variety of skills and logical problem-solving methods. kinhthu aims to share the following article to help you enhance your knowledge and skills in order to achieve your goals.

A. Overview of knowledge and problem-solving methods:

Chemical substances that can reduce metal oxides: Al, CO, H2
CO + M2On → 2M + nCO2
nH2 + M2On → 2M + nH2O

Conditions: Metal oxides that are below aluminum in the reactivity series are reduced by the given reducing agents.

Thermal reaction of aluminum: 2yAl + 3FexOy → yAl2O3 + 3xFe

1. Completely reducing a metal oxide using CO or H2:

Given data: Mass of oxide or reducing agent (CO, H2), and the resulting metal.

Steps to solve:

1. Convert the given data into number of moles.

2. Write the balanced chemical equation.

3. Determine the mole ratios of the reactants and products based on the known number of moles.

4. Calculate according to the requirements of the problem and draw conclusions.

Example 1:

When 32g of CuO is completely reduced by H2 gas, producing 32g of Cu. Calculate the volume of H2 gas required.

We have nCu = 0.5 mol

Using the chemical reaction: CuO + H2 → Cu + H2O

Calculate nH2 = 0.5 mol ➔ V = 0.5 x 22.4 = 11.2 liters

2. Reducing a mixture of two metal oxides using CO or H2:

Data provided: Total mass of oxides or resulting metals.

Steps to solve:

1. Convert the given data into number of moles for each oxide.

2. Write the balanced chemical equation for each reaction.

3. Calculate the mole ratios of the reactants and products based on the known number of moles for each oxide.

4. Solve the system of equations for each oxide to find the masses.

Example 2:

When 32g mixture of CuO and Fe2O3 are completely reduced by H2 gas, producing 9g of water. Determine the percentage mass of CuO and Fe2O3 in the mixture.

We have %CuO = 50% and %Fe2O3 = 50%

3. Reducing a mixture of multiple metal oxides using CO or H2:

Data provided: Mass of oxides or resulting metals. Volume of H2 gas, CO, or mass of CO2, H2O.

Steps to solve:

1. Convert the given data into number of moles.

2. Write the balanced chemical equation.

3. Determine the number of moles for each component based on the chemical reaction.

4. Calculate the mass of oxygen in the oxides and the total mass of the mixture.

5. Calculate according to the requirements of the problem and draw conclusions.

Example 3:

When 17.6g mixture of Fe, FeO, and Fe2O3 are completely reduced by 4.48 liters of H2 gas, calculate the mass of iron obtained.

We find the mass of iron obtained as 14.4g.

4. Determining the formula of iron oxide:

Example 4: Given 0.3 mol of FexOy reacting with aluminum to produce 0.4 mol of Al2O3, determine the formula of iron oxide as Fe3O4.