Problem 92 - Introductory Chemistry Atoms First

Question

Write the balanced equation for the preparation of iron(III) oxide from iron metal and oxygen gas. What type of reaction is this?

Step-by-Step Solution

Answer

The balanced equation for the preparation of iron(III) oxide from iron metal and oxygen gas is \(4Fe + 3O_2 \rightarrow 2Fe_2O_3\). The type of reaction is synthesis or combination.

Step 1: Write the unbalanced equation using chemical symbols and formulas

To create the unbalanced equation, we need to identify the chemical symbols for iron, oxygen, and iron(III) oxide. Iron is represented by Fe, oxygen by O2, and iron(III) oxide by Fe2O3. So, the unbalanced equation for this reaction is: Fe + O2 → Fe2O3

Step 2: Balance the chemical equation

To balance the equation, we need to ensure that there are equal numbers of each atom on both sides of the equation. In this case, we can see that there are 2 iron atoms in Fe2O3 and 3 oxygen atoms in Fe2O3, which is different from the number of iron and oxygen atoms on the left side of the equation. To balance the equation: 4Fe + 3O2 → 2Fe2O3 Now, both sides of the equation have 4 iron atoms and 6 oxygen atoms, so the equation is balanced.

Step 3: Determine the type of reaction

This reaction can be classified as a synthesis or combination reaction. In this type of reaction, two or more substances combine to form a more complex substance. In this case, iron (Fe) and oxygen (O2) are combining to form iron(III) oxide (Fe2O3). So the balanced equation for the preparation of iron(III) oxide from iron metal and oxygen gas is: 4Fe + 3O2 → 2Fe2O3 The type of reaction is synthesis or combination.

Key Concepts

Chemical Reaction Types

Understanding chemical reactions is fundamental to grasping the intricacies of chemistry. These reactions can be classified into various types based on how substances interact to form new products. Among the most common types of chemical reactions are synthesis, decomposition, single displacement, double displacement, and combustion.

In a synthesis reaction, two or more reactants combine to form a single product. Decomposition reactions involve a single compound breaking down into two or more simpler substances. Single displacement reactions see an element displacing another in a compound, whereas in double displacement reactions, ions or bonds are exchanged between two compounds. Combustion reactions involve a substance reacting with oxygen to produce heat and light, typically yielding CO₂ and H₂O as products.

Synthesis Reactions

A synthesis reaction, also known as a combination reaction, is a process where multiple reactants bond together to form a single, more complex product. This type of reaction is characterized by its simplicity; it typically involves straightforward mechanisms where atoms or molecules join, resulting in a new substance with different properties from the original reactants.

For instance, when iron (Fe) combines with oxygen (O₂) in the environment, under specific conditions, they form iron(III) oxide (Fe₂O₃). This process is a classic example of a synthesis reaction where two elements, a metal, and a nonmetal, react to produce a compound, showcasing how synthesis reactions can result in entirely new material properties, such as rust formation from pure iron metal.

Stoichiometry

Stoichiometry is a section of chemistry that deals with the quantitative relationships of the reactants and products in a chemical reaction. It is based on the law of conservation of mass, which states that in a chemical reaction, matter is neither created nor destroyed. This principle ensures that the number of atoms for each element must remain constant through the reaction, resulting in a balanced chemical equation.

The stoichiometry of a balanced equation represents the ratio of reactants to products. In our example of forming iron(III) oxide from iron metal and oxygen gas, the stoichiometry is 4:3:2, indicating that four moles of iron react with three moles of oxygen gas to yield two moles of iron(III) oxide. Mastery of stoichiometry is crucial for predicting the outcome of reactions, understanding reaction yields, and conducting accurate chemical measurements in a laboratory setting.