Decomposition reactions are chemical reactions in which a single compound breaks down into two or more simpler substances. These reactions are the opposite of combination reactions, where two or more substances combine to form a single compound. In a decomposition reaction, energy in the form of heat, light, or electricity is often required to break the chemical bonds in the compound.

General Form of Decomposition Reactions

The general form of a decomposition reaction can be represented as:

AB → A + B

Where "AB" is the compound that decomposes into the simpler substances "A" and "B".

Types of Decomposition Reactions

There are several types of decomposition reactions, including:

Thermal decomposition: Involves the breakdown of a compound due to heating.
Electrolytic decomposition: Occurs when an electric current is passed through a compound, causing it to decompose.
Photodecomposition: Involves the decomposition of a compound by light energy.

Examples of Decomposition Reactions

Some common examples of decomposition reactions include:

1. Decomposition of hydrogen peroxide:

2H₂O₂ → 2H₂O + O₂

Hydrogen peroxide decomposes into water and oxygen gas.

2. Decomposition of calcium carbonate:

CaCO₃ → CaO + CO₂

Calcium carbonate decomposes into calcium oxide and carbon dioxide gas.

Study Guide for Decomposition Reactions

When studying decomposition reactions, consider the following key points:

Understand the general form of a decomposition reaction: AB → A + B
Learn the different types of decomposition reactions: thermal, electrolytic, and photodecomposition.
Memorize common examples of decomposition reactions, such as the decomposition of hydrogen peroxide and calcium carbonate.
Practice balancing chemical equations for decomposition reactions.
Understand the role of energy in decomposition reactions and how it affects the breaking of chemical bonds.

Remember, decomposition reactions are important in various industrial processes and natural phenomena, making them a crucial topic in chemistry.

◂Chemistry Worksheets and Study Guides High School. Chemical Reactions

Vocabulary/Answer key

Chemical Reactions

Vocabulary/Answer key

Chemical Reactions

Vocabulary/Answer key

Chemical Reactions

The resources above cover the following skills:

Skills And Processes: The student will demonstrate ways of thinking and acting inherent in the practice of science. The student will use the language and instruments of science to collect, organize, interpret, calculate, and communicate information.

The student will pose scientific questions and suggest investigative approaches to provide answers to questions.

The student will test a working hypothesis. (NTB)

The student will demonstrate that data analysis is a vital aspect of the process of scientific inquiry and communication.

The student will organize data appropriately using techniques such as tables, graphs, and webs (for graphs: axes labeled with appropriate quantities, appropriate units on axes, axes labeled with appropriate intervals, independent and dependent variables on correct axes, appropriate title).

Concepts Of Chemistry: The student will demonstrate the ability to use scientific skills and processes (Core Learning Goal 1) to explain composition and interactions of matter in the world in which we live.

The student will explain that atoms have structure and this structure serves as the basis for the properties of elements and the bonds that they form.

The student will explain how atoms interact with other atoms through the transfer and sharing of electrons in the formation of chemical bonds.

The student will explain how and why substances are represented by formulas.

The student will show that chemical reactions can be represented by symbolic or word equations that specify all reactants and products involved.

The student will explain that matter undergoes transformations, resulting in products that are different from the reactants.

The student will describe the general types of chemical reactions.

The student will balance simple equations (not to include redox reactions).

The student will demonstrate that adjusting quantities of reactants may affect the amounts of products formed.

The student will recognize that chemical reactions occur at different speeds.