Question

Write the equilibrium equation between iron(III) sulfate as the reactant and iron(III) oxide and sulfur trioxide as the products.

Short answer

The balanced equation is \( \text{Fe}_2(\text{SO}_4)_3 \leftrightarrow \text{Fe}_2\text{O}_3 + 3\text{SO}_3 \).

Step-by-step solution

Write the Chemical Formula of Reactants and Products

The reactant is iron(III) sulfate, expressed as \( \text{Fe}_2(\text{SO}_4)_3 \). The products are iron(III) oxide, which is \( \text{Fe}_2\text{O}_3 \), and sulfur trioxide, which is \( \text{SO}_3 \).

Balance the Number of Iron (Fe) Atoms

Each side of the equation must have an equal number of iron atoms. In this case, we have \( 2 \) iron atoms on both sides, so the iron atoms are balanced.

Balance the Number of Sulfur (S) Atoms

Iron(III) sulfate has \( 3 \) sulfate ions, each containing \( 1 \) sulfur atom, making a total of \( 3 \) sulfur atoms. We need \( 3 \) \( \text{SO}_3 \) molecules on the product side to balance the sulfur atoms since each \( \text{SO}_3 \) contains \( 1 \) sulfur atom: \( 3 \times \text{SO}_3 \).

Balance the Number of Oxygen (O) Atoms

On the reactant side, there are \( 3 \times 4 = 12 \) oxygen atoms in iron(III) sulfate. On the product side, \( \text{Fe}_2\text{O}_3 \) contributes \( 3 \) oxygen atoms, and \( 3 \times \text{SO}_3 \) contributes \( 3 \times 3 = 9 \) oxygen atoms. Together, they make \( 12 \) oxygen atoms, thus balancing the equation.

Write the Balanced Equation

Now, we can write the balanced chemical equation: \[ \text{Fe}_2(\text{SO}_4)_3 \leftrightarrow \text{Fe}_2\text{O}_3 + 3\text{SO}_3 \].

Key concepts

Balancing Chemical Equations

Balancing chemical equations is a fundamental skill in chemistry. It ensures that the same number of each type of atom appears on both sides of a chemical reaction. In other words, the mass is conserved during the reaction. To achieve a balanced equation, follow these steps:
- Write down the unbalanced equation by listing reactants and products.
- Count the number of atoms for each element on both sides.
- Use coefficients to balance each type of atom, adjusting them until each element has the same number of atoms on the reactant and product sides.
It's like a puzzle where pieces represent atoms. Once the number of each type of atom is the same on both sides, the equation is balanced. This concept is crucial to predict the amount of products formed in a reaction and to understand the reaction's dynamics.

Iron(III) Sulfate

Iron(III) sulfate is a compound that consists of iron and sulfate ions. Its chemical formula is \( \text{Fe}_2(\text{SO}_4)_3 \), and it is composed of two iron (Fe) atoms and three sulfate \((\text{SO}_4)\) ions.
The iron in this compound is in the +3 oxidation state, indicated by the Roman numeral III. This means each iron atom has donated three electrons, which affects how it bonds with other ions.
Sulfate is a polyatomic ion, meaning it is a charged molecule made up of more than one atom, specifically sulphur and oxygen. Understanding the structure and composition of iron(III) sulfate is essential to predict its behavior in chemical reactions and to balance chemical equations properly.

Chemical Reactions

Chemical reactions involve the transformation of reactants into products, often with energy changes and the reconfiguration of atoms. A chemical equation is a symbolic representation of this process. For example, the reaction of iron(III) sulfate decomposing into iron(III) oxide and sulfur trioxide is represented as:
\[\text{Fe}_2(\text{SO}_4)_3 \leftrightarrow \text{Fe}_2\text{O}_3 + 3\text{SO}_3\]
This equation illustrates an equilibrium, meaning that both the forward and reverse reactions occur at equal rates. Thus, the quantities of reactants and products remain constant over time.
In a chemical reaction, bonds between atoms in the reactants are broken and new bonds to create the products are formed. By balancing the equation, we ensure that the atoms are conserved, which is in line with the Law of Conservation of Mass. Understanding this concept allows chemists to build on predictions and synthesize new materials efficiently.