Problem 116 - Introductory Chemistry Atoms First

Question

Heating magnesium carbonate results in the production of carbon dioxide and magnesium oxide. Write the balanced equation for this process, and indicate the type of reaction.

Step-by-Step Solution

Answer

The balanced chemical equation for the decomposition of magnesium carbonate is: \(MgCO_3 \rightarrow CO_2 + MgO\). The type of reaction is a decomposition reaction.

Step 1: Write the unbalanced chemical equation

First, write the unbalanced chemical equation using the reactant, magnesium carbonate (MgCO3), and the products, carbon dioxide (CO2) and magnesium oxide (MgO). MgCO3 → CO2 + MgO

Step 2: Balance the chemical equation

To balance the equation, we need to make sure that all the atoms in the reactants are equal to the atoms in the products. In this case, the equation is already balanced: MgCO3 → CO2 + MgO There is one magnesium atom on both sides, one carbon atom on both sides, and three oxygen atoms on both sides.

Step 3: Determine the type of reaction

Now we need to determine the type of reaction. For this reaction, magnesium carbonate is being heated up and breaking down into two simpler products, carbon dioxide and magnesium oxide. This is an example of a decomposition reaction, as a single reactant is breaking down into multiple products.

Step 4: Final Answer

The balanced chemical equation for this process is: MgCO3 → CO2 + MgO And the type of reaction is a decomposition reaction.

Key Concepts

Decomposition Reaction

A decomposition reaction is a type of chemical reaction where a single compound breaks down into two or more simpler substances. This can be triggered by various conditions such as heating, as in the case of magnesium carbonate (MgCO₃), exposure to light, or through electrolysis. During heating, magnesium carbonate decomposes into magnesium oxide (MgO) and carbon dioxide (CO₂).

Understanding decomposition reactions is crucial for students because it lays the foundation for recognizing reaction patterns and predicting the outcome of other reactions. It can also play a significant role in industrial processes, such as the production of lime from limestone or the breakdown of organic matter in composting. When studying these reactions, it's essential to remember that energy is often required to break the bonds in the reactant molecule in order to form the products.

Chemical Reaction Types

Chemical reactions can be classified into various types, each showcasing different patterns of reactants and products. These include synthesis reactions, where simple substances combine to form more complex compounds; decomposition reactions discussed earlier; single replacement reactions, which involve an element replacing another in a compound; and double replacement reactions, where parts of two compounds swap to create new compounds.

Recognizing the type of reaction facilitates the understanding of energy changes during the process and helps predict the products. For instance, in the exercise, the decomposition of magnesium carbonate to form magnesium oxide and carbon dioxide required energy input, in the form of heat. This understanding is not just academic but also has practical applications, such as in environmental science to understand greenhouse gas production or in materials science for the synthesis of new compounds.

Stoichiometry

Stoichiometry is the quantitative aspect of chemical reactions, dealing with the relationships between the amounts of reactants and products. It's based on the conservation of mass and the ratios provided by balanced chemical equations. To solve stoichiometric problems, one must first write a correctly balanced equation, as seen in the decomposition of magnesium carbonate.

Next, using the coefficients from the balanced equation, one can calculate moles, mass, volume, or the number of particles of the reactants and products involved in the reaction. For example, if you know the mass of magnesium carbonate heated, you can use stoichiometry to determine the amount of carbon dioxide and magnesium oxide formed. This concept is vital in fields such as chemical engineering, medicine, and environmental science, where precise amounts of substances are crucial for processes, formulations, or compliance with regulations.